Catch a one-past-the-end write into msg[]'s neighbour

Review found the new self-test blind to a store at msg[sizeof(msg)]: it
lands in the adjacent contenttype field, which no assertion read, and an
intra-struct overflow is invisible to ASan and _FORTIFY_SOURCE. Check the
neighbour after every call, and add the exact-fit case the block lacked.

Correct the contract comment too: msg is not purely diagnostic, it
round-trips through the cache as X-StatusMessage.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Signed-off-by: Xavier Roche <roche@httrack.com>

.github/workflows/windows-build.yml

@@ -225,8 +225,9 @@ jobs:
 
           # Every gate here exits 77, so an all-skipped suite would report green having
           # tested nothing: pin the skips, and floor the passes in case the glob empties.
-          # footer-overflow skips on Windows (needs a path past MAX_PATH); crange pending #581.
-          expected_skips=" 01_engine-footer-overflow.test 48_local-crange-memresume.test 71_local-crange-repaircache.test"
+          # footer-overflow skips on Windows (needs a path past MAX_PATH); crange pending #581;
+          # webdav-mime needs a reapable background listener, which MSYS cannot give it.
+          expected_skips=" 01_engine-footer-overflow.test 48_local-crange-memresume.test 71_local-crange-repaircache.test 79_local-proxytrack-webdav-mime.test"
           [ "$pass" -ge 90 ] || { echo "::error::only $pass tests passed ($skip skipped)"; exit 1; }
           [ "$skipped" = "$expected_skips" ] || { echo "::error::unexpected skips:$skipped"; exit 1; }
           [ "$fail" -eq 0 ] || { echo "::error::failing:$failed"; exit 1; }

configure.ac

@@ -100,7 +100,8 @@ AX_CHECK_COMPILE_FLAG([-fstack-protector-strong], [DEFAULT_CFLAGS="$DEFAULT_CFLA
 	[AX_CHECK_COMPILE_FLAG([-fstack-protector], [DEFAULT_CFLAGS="$DEFAULT_CFLAGS -fstack-protector"], [], [-Werror])], [-Werror])
 AX_CHECK_COMPILE_FLAG([-fstack-clash-protection], [DEFAULT_CFLAGS="$DEFAULT_CFLAGS -fstack-clash-protection"], [], [-Werror])
 AX_CHECK_COMPILE_FLAG([-fcf-protection], [DEFAULT_CFLAGS="$DEFAULT_CFLAGS -fcf-protection"], [], [-Werror])
-AX_CHECK_LINK_FLAG([-Wl,--discard-all], [DEFAULT_LDFLAGS="$DEFAULT_LDFLAGS -Wl,--discard-all"])
+# No --discard-all: it drops the local symbols naming every static function, so
+# a trace misattributes them to the nearest surviving global. Costs 0.6% size.
 AX_CHECK_LINK_FLAG([-Wl,--no-undefined], [DEFAULT_LDFLAGS="$DEFAULT_LDFLAGS -Wl,--no-undefined"])
 AX_CHECK_LINK_FLAG([-Wl,-z,relro,-z,now], [DEFAULT_LDFLAGS="$DEFAULT_LDFLAGS -Wl,-z,relro,-z,now"])
 AX_CHECK_LINK_FLAG([-Wl,-z,noexecstack], [DEFAULT_LDFLAGS="$DEFAULT_LDFLAGS -Wl,-z,noexecstack"])
@@ -127,8 +128,8 @@ AX_CHECK_LINK_FLAG([-pie], [LDFLAGS_PIE="-pie"])
 AC_SUBST([CFLAGS_PIE])
 AC_SUBST([LDFLAGS_PIE])
 
-## -rdynamic must be a link flag; DEFAULT_CFLAGS (AM_CPPFLAGS) never reaches the linker.
-AX_CHECK_LINK_FLAG([-rdynamic], [DEFAULT_LDFLAGS="$DEFAULT_LDFLAGS -rdynamic"])
+# Ties a crash trace from a stripped build back to its separate debug symbols.
+AX_CHECK_LINK_FLAG([-Wl,--build-id], [DEFAULT_LDFLAGS="$DEFAULT_LDFLAGS -Wl,--build-id"])
 
 ### Check for -fvisibility=hidden support
 gl_VISIBILITY

html/server/option2b.html

@@ -103,7 +103,7 @@ ${LANG_Q3}
 <tr><td>
 	<table width="100%">
 	<tr><td align="left">
-	<input type="submit" value="${LANG_OK]" 
+	<input type="submit" value="${LANG_OK}"
 ${do:output-mode:html-urlescaped}
 		onClick="if (confirm(str_replace(str_replace('${LANG_DIAL7}', '%20', ' '), '%0a', ' '))) { form.closeme.value=1; form.submit(); } return false;"
 ${do:output-mode:}

html/server/step4.html

@@ -121,9 +121,9 @@ httrack \
 	--quiet \
 	--build-top-index \
 	${test:todo:--mirror:--mirror:--mirror-wizard:--get:--mirrorlinks:--testlinks:--continue:--update}
-	${urls}
-	${test:filelist:-%L "}${filelist}${test:filelist:"}
-	--path "${html:path}/${html:projname}" 
+	${unquoted:urls}
+	${test:filelist:-%L "}${arg:filelist}${test:filelist:"}
+	--path "${arg:path}/${arg:projname}" 
 \
 	${test:parseall:--near}
 	${test:link:--test}
@@ -131,7 +131,7 @@ httrack \
 	${test:htmlfirst::--priority=7}
 \
 ${do:if-not-empty:BuildString}
-	--structure "${BuildString}"
+	--structure "${arg:BuildString}"
 ${do:end-if}
 	${test:build:-N0:-N0:-N1:-N2:-N3:-N4:-N5:-N100:-N101:-N102:-N103:-N104:-N105:-N99:-N199:}
 \
@@ -150,29 +150,30 @@ ${do:end-if}
 	${test:travel3::--keep-links=0:--keep-links:--keep-links=3:--keep-links=4}
 	${test:windebug:--debug-headers}
 \
-	${test:connexion:--sockets=}${connexion}
+	${test:connexion:--sockets=}${unquoted:connexion}
 	${test:ka:--keep-alive}
-	${test:timeout:--timeout=}${timeout}
+	${test:timeout:--timeout=}${unquoted:timeout}
 	${test:remt:--host-control=1}
-	${test:retry:--retries=}${retry}
-	${test:rate:--min-rate=}${rate}
+	${test:retry:--retries=}${unquoted:retry}
+	${test:rate:--min-rate=}${unquoted:rate}
 	${test:rems:--host-control=2}
 \
-	${test:depth:--depth=}${depth}
-	${test:depth2:--ext-depth=}${depth2}
-	${test:maxhtml:--max-files=,}${maxhtml}
-	${test:othermax:--max-files=}${othermax}
-	${test:sizemax:--max-files=}${sizemax}
-	${test:pausebytes:--max-pause=}${pausebytes}
-	${test:maxtime:--max-time=}${maxtime}
-	${test:maxrate:--max-rate=}${maxrate}
-	${test:maxconn:--connection-per-second=}${maxconn}
-	${test:maxlinks:--advanced-maxlinks=}${maxlinks}
+	${test:depth:--depth=}${unquoted:depth}
+	${test:depth2:--ext-depth=}${unquoted:depth2}
+${/* -m<n> resets the html limit, so the bare form must precede the -m,<n> one */}
+	${test:othermax:--max-files=}${unquoted:othermax}
+	${test:maxhtml:--max-files=,}${unquoted:maxhtml}
+	${test:sizemax:--max-size=}${unquoted:sizemax}
+	${test:pausebytes:--max-pause=}${unquoted:pausebytes}
+	${test:maxtime:--max-time=}${unquoted:maxtime}
+	${test:maxrate:--max-rate=}${unquoted:maxrate}
+	${test:maxconn:--connection-per-second=}${unquoted:maxconn}
+	${test:maxlinks:--advanced-maxlinks=}${unquoted:maxlinks}
 \
-	--user-agent "${html:user}"
-	--footer "${html:footer}"
+	--user-agent "${arg:user}"
+	--footer "${arg:footer}"
 \
-	${url2}
+	${unquoted:url2}
 \
 	${test:cookies:--cookies=0:}
 	${test:parsejava:--parse-java=0:}
@@ -181,20 +182,20 @@ ${do:end-if}
 	${test:keepwww:--keep-www-prefix}
 	${test:keepslashes:--keep-double-slashes}
 	${test:keepqueryorder:--keep-query-order}
-	${test:cookiesfile:--cookies-file "}${html:cookiesfile}${test:cookiesfile:"}
-	${test:pausefiles:--pause "}${pausefiles}${test:pausefiles:"}
-	${test:stripquery:--strip-query "}${html:stripquery}${test:stripquery:"}
+	${test:cookiesfile:--cookies-file "}${arg:cookiesfile}${test:cookiesfile:"}
+	${test:pausefiles:--pause "}${arg:pausefiles}${test:pausefiles:"}
+	${test:stripquery:--strip-query "}${arg:stripquery}${test:stripquery:"}
 	${test:toler:--tolerant}
 	${test:http10:--http-10}
 	${test:cache2:--store-all-in-cache}
 	${test:warc:--warc}
-	${test:warcfile:--warc-file "}${html:warcfile}${test:warcfile:"}
+	${test:warcfile:--warc-file "}${arg:warcfile}${test:warcfile:"}
 	${test:norecatch:--do-not-recatch}
 	${test:logf:--single-log}
 	${test:logtype:::--extra-log:--debug-log}
 	${test:index:--index=0:}
 	${test:index2:--search-index=0:--search-index}
-	${test:prox:--proxy "}${do:if-not-empty:prox}${test:proxytype::socks5:connect}${test:proxytype:\3A//}${do:end-if}${do:output-mode:html}${prox}${test:prox:\3A}${portprox}${test:prox:"}
+	${test:prox:--proxy "}${do:if-not-empty:prox}${test:proxytype::socks5:connect}${test:proxytype:\3A//}${do:end-if}${do:output-mode:html}${arg:prox}${test:prox:\3A}${arg:portprox}${test:prox:"}
 	${test:ftpprox:--httpproxy-ftp=0:--httpproxy-ftp}
 </textarea>
 
@@ -213,7 +214,7 @@ ParseAll=${ztest:parseall:0:1}
 HTMLFirst=${ztest:htmlfirst:0:1}
 Cache=${ztest:cache:0:1}
 NoRecatch=${ztest:norecatch:0:1}
-Dos=${dos
+Dos=${dos}
 Index=${ztest:index:0:1}
 WordIndex=${ztest:index2:0:1}
 Log=${ztest:logf:0:1:2}

src/Makefile.am

@@ -32,7 +32,9 @@ AM_LDFLAGS = \
 
 bin_PROGRAMS = proxytrack httrack htsserver
 
-httrack_LDADD = $(THREADS_LIBS) libhttrack.la
+httrack_SOURCES = httrack.c htsbacktrace.c htsbacktrace.h
+# $(DL_LIBS): dladdr() in the crash handler, still in libdl on pre-2.34 glibc.
+httrack_LDADD = $(THREADS_LIBS) $(DL_LIBS) libhttrack.la
 htsserver_LDADD = $(THREADS_LIBS) $(SOCKET_LIBS) libhttrack.la
 proxytrack_LDADD = $(THREADS_LIBS) $(SOCKET_LIBS)
 
@@ -47,6 +49,7 @@ htsserver_LDFLAGS = $(AM_LDFLAGS) $(LDFLAGS_PIE)
 lib_LTLIBRARIES = libhttrack.la
 
 htsserver_SOURCES = htsserver.c htsserver.h htsweb.c htsweb.h \
+	htscmdline.c htscmdline.h \
 	htsurlport.c htsurlport.h
 proxytrack_SOURCES = proxy/main.c \
 	proxy/proxytrack.c proxy/store.c \
@@ -60,7 +63,7 @@ whttrackrun_SCRIPTS = webhttrack
 libhttrack_la_SOURCES =  htscore.c htsparse.c htsback.c htscache.c \
 	htscache_selftest.c htsdns_selftest.c htsselftest.c \
 	htscatchurl.c htsfilters.c htsftp.c htshash.c coucal/coucal.c \
-	htshelp.c htslib.c htsurlport.c htscoremain.c \
+	htscmdline.c htshelp.c htslib.c htsurlport.c htscoremain.c \
 	htsname.c htsrobots.c htstools.c htswizard.c \
 	htsalias.c htsthread.c htsindex.c htsbauth.c \
 	htsmd5.c htscodec.c htswarc.c htsproxy.c htszlib.c htswrap.c htsconcat.c \
@@ -69,7 +72,7 @@ libhttrack_la_SOURCES =  htscore.c htsparse.c htsback.c htscache.c \
 	minizip/ioapi.c minizip/mztools.c minizip/unzip.c minizip/zip.c \
 	hts-indextmpl.h htsalias.h htsback.h htsbase.h htssafe.h \
 	htsbasenet.h htsbauth.h htscache.h htscache_selftest.h htsdns_selftest.h htsselftest.h htscatchurl.h  \
-	htsconfig.h htscore.h htsparse.h htscoremain.h htsdefines.h  \
+	htscmdline.h htsconfig.h htscore.h htsparse.h htscoremain.h htsdefines.h  \
 	htsfilters.h htsftp.h htsglobal.h htshash.h coucal/coucal.h \
 	htshelp.h htsindex.h htslib.h htsurlport.h htsmd5.h \
 	htsmodules.h htsname.h htsnet.h htssniff.h \

src/htsback.c

@@ -541,9 +541,15 @@ static int create_back_tmpfile(httrackp *opt, lien_back *const back,
                                const char *ext) {
   // do not use tempnam() but a regular filename
   back->tmpfile_buffer[0] = '\0';
-  if (back->url_sav != NULL && back->url_sav[0] != '\0') {
-    snprintf(back->tmpfile_buffer, sizeof(back->tmpfile_buffer), "%s.%s",
-             back->url_sav, ext);
+  if (back->url_sav[0] != '\0') {
+    /* same capacity as url_sav, so truncation drops the extension and aliases
+       the temp name onto the live file that back_finalize_backup() UNLINKs */
+    if (!sprintfbuff(back->tmpfile_buffer, "%s.%s", back->url_sav, ext)) {
+      hts_log_print(opt, LOG_WARNING, "temporary filename too long for %s",
+                    back->url_sav);
+      back->tmpfile_buffer[0] = '\0';
+      return -1;
+    }
     back->tmpfile = back->tmpfile_buffer;
     if (structcheck(back->tmpfile) != 0) {
       hts_log_print(opt, LOG_WARNING, "can not create directory to %s",
@@ -551,8 +557,15 @@ static int create_back_tmpfile(httrackp *opt, lien_back *const back,
       return -1;
     }
   } else {
-    snprintf(back->tmpfile_buffer, sizeof(back->tmpfile_buffer), "%s/tmp%d.%s",
-             StringBuff(opt->path_html_utf8), opt->state.tmpnameid++, ext);
+    /* truncation here would collide distinct tmpnameid's onto one name */
+    if (!sprintfbuff(back->tmpfile_buffer, "%s/tmp%d.%s",
+                     StringBuff(opt->path_html_utf8), opt->state.tmpnameid++,
+                     ext)) {
+      hts_log_print(opt, LOG_WARNING, "temporary filename too long in %s",
+                    StringBuff(opt->path_html_utf8));
+      back->tmpfile_buffer[0] = '\0';
+      return -1;
+    }
     back->tmpfile = back->tmpfile_buffer;
   }
   /* OK */
@@ -887,8 +900,7 @@ int back_finalize(httrackp * opt, cache_back * cache, struct_back * sback,
               HTS_STAT.stat_bytes += back[p].r.size;
               HTS_STAT.stat_files++;
               hts_log_print(opt, LOG_TRACE, "added file %s%s => %s",
-                            back[p].url_adr, back[p].url_fil,
-                            back[p].url_sav != NULL ? back[p].url_sav : "");
+                            back[p].url_adr, back[p].url_fil, back[p].url_sav);
             }
             if ((!back[p].r.notmodified) && (opt->is_update)) {
               HTS_STAT.stat_updated_files++;    // page modifiée
@@ -2302,26 +2314,24 @@ int back_add(struct_back *sback, httrackp *opt, cache_back *cache,
               && slot_can_be_finalized(opt, &back[i]);
             int may_serialize = slot_can_be_cached_on_disk(&back[i]);
 
-            hts_log_print(opt, LOG_DEBUG,
-                          "back[%03d]: may_clean=%d, may_finalize_disk=%d, may_serialize=%d:"
-                          LF "\t"
-                          "finalized(%d), status(%d), locked(%d), delayed(%d), test(%d), "
-                          LF "\t"
-                          "statuscode(%d), size(%d), is_write(%d), may_hypertext(%d), "
-                          LF "\t" "contenttype(%s), url(%s%s), save(%s)", i,
-                          may_clean, may_finalize, may_serialize,
-                          back[i].finalized, back[i].status, back[i].locked,
-                          IS_DELAYED_EXT(back[i].url_sav), back[i].testmode,
-                          back[i].r.statuscode, (int) back[i].r.size,
-                          back[i].r.is_write, may_be_hypertext_mime(opt,
-                                                                    back[i].r.
-                                                                    contenttype,
-                                                                    back[i].
-                                                                    url_fil),
-                          /* */
-                          back[i].r.contenttype, back[i].url_adr,
-                          back[i].url_fil,
-                          back[i].url_sav ? back[i].url_sav : "<null>");
+            hts_log_print(
+                opt, LOG_DEBUG,
+                "back[%03d]: may_clean=%d, may_finalize_disk=%d, "
+                "may_serialize=%d:" LF "\t"
+                "finalized(%d), status(%d), locked(%d), delayed(%d), "
+                "test(%d), " LF "\t"
+                "statuscode(%d), size(%d), is_write(%d), may_hypertext(%d), " LF
+                "\t"
+                "contenttype(%s), url(%s%s), save(%s)",
+                i, may_clean, may_finalize, may_serialize, back[i].finalized,
+                back[i].status, back[i].locked, IS_DELAYED_EXT(back[i].url_sav),
+                back[i].testmode, back[i].r.statuscode, (int) back[i].r.size,
+                back[i].r.is_write,
+                may_be_hypertext_mime(opt, back[i].r.contenttype,
+                                      back[i].url_fil),
+                /* */
+                back[i].r.contenttype, back[i].url_adr, back[i].url_fil,
+                back[i].url_sav);
           }
         }
       }
@@ -2857,7 +2867,8 @@ void back_wait(struct_back * sback, httrackp * opt, cache_back * cache,
               // new session
               back[i].r.ssl_con = SSL_new(openssl_ctx);
               if (back[i].r.ssl_con) {
-                const char* hostname = jump_protocol_const(back[i].url_adr);
+                /* non-const twin: the OpenSSL macro casts the qualifier away */
+                char *hostname = jump_protocol(back[i].url_adr);
                 // some servers expect the hostname on the clienthello (SNI TLS extension)
                 SSL_set_tlsext_host_name(back[i].r.ssl_con, hostname);
                 SSL_clear(back[i].r.ssl_con);

src/htsbacktrace.c

@@ -0,0 +1,238 @@
+/* ------------------------------------------------------------ */
+/*
+HTTrack Website Copier, Offline Browser for Windows and Unix
+Copyright (C) 1998 Xavier Roche and other contributors
+
+SPDX-License-Identifier: GPL-3.0-or-later
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program. If not, see <http://www.gnu.org/licenses/>.
+
+Ethical use: we kindly ask that you NOT use this software to harvest email
+addresses or to collect any other private information about people. Doing so
+would dishonor our work and waste the many hours we have spent on it.
+
+Please visit our Website: http://www.httrack.com
+*/
+
+/* ------------------------------------------------------------ */
+/* File: crash backtrace printer                                 */
+/* Author: Xavier Roche                                          */
+/* ------------------------------------------------------------ */
+
+/* Before every header: glibc gates dladdr() on it. */
+#if defined(__linux) && !defined(_GNU_SOURCE)
+#define _GNU_SOURCE
+#endif
+
+#include "htsbacktrace.h"
+
+#include "htsglobal.h"
+
+#include <stdlib.h>
+#include <string.h>
+#ifdef _WIN32
+#include <io.h> /* write */
+#endif
+#ifdef HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+#if (defined(__linux) && defined(HAVE_EXECINFO_H))
+#include <dlfcn.h>
+#include <errno.h>
+#include <execinfo.h>
+#include <signal.h>
+#include <time.h>
+#include <sys/wait.h>
+#define USES_BACKTRACE
+#endif
+
+#ifdef USES_BACKTRACE
+#define BT_MAX_FRAMES 64     /* frames we try to name */
+#define BT_MAX_MODULES 8     /* distinct modules, one child each */
+#define BT_HEX_SIZE 19       /* "0x" + 16 nibbles + NUL */
+#define BT_PATH_SIZE 1024    /* module path; longer is skipped */
+#define BT_WAIT_TICKS 300    /* 10ms ticks, shared: cap a slow child */
+#define BT_NO_SYMBOLIZER 127 /* child exit: execvp() found none */
+
+static hts_boolean symbolize_crash = HTS_TRUE;
+
+/* "0x"-prefixed hex: the handler must stay stdio-free. */
+static void print_hex(char *buffer, uintptr_t value) {
+  static const char digits[] = "0123456789abcdef";
+  size_t i = 2, a, b;
+
+  buffer[0] = '0';
+  buffer[1] = 'x';
+  do {
+    buffer[i++] = digits[value & 0xf];
+    value >>= 4;
+  } while (value != 0);
+  buffer[i] = '\0';
+  for (a = 2, b = i - 1; a < b; a++, b--) {
+    const char c = buffer[a];
+
+    buffer[a] = buffer[b];
+    buffer[b] = c;
+  }
+}
+
+/* HTS_FALSE if src does not fit: a truncated module path would point the
+   symbolizer at the wrong file. */
+static hts_boolean copy_bounded(char *dest, size_t size, const char *src) {
+  size_t i;
+
+  for (i = 0; i < size - 1 && src[i] != '\0'; i++) {
+    dest[i] = src[i];
+  }
+  dest[i] = '\0';
+  return src[i] == '\0' ? HTS_TRUE : HTS_FALSE;
+}
+
+/* Run the symbolizer on argv, output on fd, within *budget ticks. HTS_FALSE
+   only if none could be run at all; otherwise silent, the raw trace stands. */
+static hts_boolean spawn_symbolizer(char **argv, int fd, int *budget) {
+  const pid_t pid = fork();
+  int status = 0;
+
+  if (pid == -1)
+    return HTS_FALSE;
+  if (pid == 0) {
+    static char llvm_prog[] = "llvm-symbolizer";
+    static char llvm_opts[] = "-p";
+
+    dup2(fd, 1); /* both symbolizers write on stdout */
+    execvp(argv[0], argv);
+    argv[0] = llvm_prog; /* an LLVM-only install ships no addr2line */
+    argv[1] = llvm_opts;
+    execvp(argv[0], argv);
+    _exit(BT_NO_SYMBOLIZER);
+  }
+  for (; *budget > 0; (*budget)--) {
+    const struct timespec tick = {0, 10 * 1000 * 1000};
+    const pid_t reaped = waitpid(pid, &status, WNOHANG);
+
+    if (reaped == pid)
+      return WIFEXITED(status) && WEXITSTATUS(status) == BT_NO_SYMBOLIZER
+                 ? HTS_FALSE
+                 : HTS_TRUE;
+    if (reaped == -1 && errno != EINTR)
+      return HTS_TRUE;
+    nanosleep(&tick, NULL);
+  }
+  kill(pid, SIGKILL);
+  waitpid(pid, NULL, 0);
+  return HTS_TRUE;
+}
+
+/* Name the frames backtrace_symbols_fd() leaves as module+offset:
+   -fvisibility=hidden keeps them out of .dynsym, but DWARF has them. dladdr()
+   is not formally async-signal-safe; accepted, this path is already fatal. */
+static void symbolize_backtrace(void *const *stack, int size, int fd) {
+  static char prog[] = "addr2line";
+  static char opts[] = "-Cfipa";
+  static char dashe[] = "-e";
+  char hex[BT_MAX_FRAMES][BT_HEX_SIZE];
+  const void *base[BT_MAX_FRAMES];
+  const char *name[BT_MAX_FRAMES];
+  hts_boolean grouped[BT_MAX_FRAMES];
+  char module[BT_PATH_SIZE];
+  char *argv[4 + BT_MAX_FRAMES + 1];
+  int budget = BT_WAIT_TICKS;
+  int i, spawned;
+
+  if (size > BT_MAX_FRAMES)
+    size = BT_MAX_FRAMES;
+
+  for (i = 0; i < size; i++) {
+    Dl_info info;
+
+    grouped[i] = HTS_TRUE; /* skipped unless dladdr() places the frame */
+    if (dladdr(stack[i], &info) == 0 || info.dli_fname == NULL ||
+        info.dli_fname[0] == '\0')
+      continue;
+    base[i] = info.dli_fbase;
+    name[i] = info.dli_fname;
+    print_hex(hex[i], (uintptr_t) ((const char *) stack[i] -
+                                   (const char *) info.dli_fbase));
+    grouped[i] = HTS_FALSE;
+  }
+
+  /* One child per module: addr2line takes a single -e. Each frame is claimed
+     once, so argc cannot exceed argv[]. */
+  for (spawned = 0; spawned < BT_MAX_MODULES; spawned++) {
+    int first, j, argc = 0;
+
+    for (first = 0; first < size && grouped[first]; first++)
+      ;
+    if (first >= size)
+      break;
+    argv[argc++] = prog;
+    argv[argc++] = opts;
+    argv[argc++] = dashe;
+    argv[argc++] = module;
+    for (j = first; j < size; j++) {
+      if (grouped[j] || base[j] != base[first])
+        continue;
+      grouped[j] = HTS_TRUE;
+      argv[argc++] = hex[j];
+    }
+    argv[argc] = NULL;
+    /* access(): skip pseudo-modules like linux-vdso, which have no file and
+       would draw nothing but an addr2line complaint. */
+    if (copy_bounded(module, sizeof(module), name[first]) &&
+        access(module, R_OK) == 0) {
+      const size_t len = strlen(module);
+
+      /* addr2line -a prints offsets only: say which module they are in. */
+      (void) (write(fd, module, len) == (ssize_t) len);
+      (void) (write(fd, ":\n", 2) == 2);
+      if (!spawn_symbolizer(argv, fd, &budget))
+        break; /* no symbolizer: stop at one header */
+    }
+  }
+}
+#endif
+
+void hts_backtrace_init(void) {
+#ifdef USES_BACKTRACE
+  symbolize_crash =
+      getenv("HTTRACK_NO_SYMBOLIZE") == NULL ? HTS_TRUE : HTS_FALSE;
+#endif
+}
+
+void hts_print_backtrace(int fd) {
+#ifdef USES_BACKTRACE
+  void *stack[256];
+  const int size = backtrace(stack, sizeof(stack) / sizeof(stack[0]));
+
+  /* A fault inside the handler lands back here: symbolizing twice interleaves
+     two traces on fd and spends a second budget. */
+  static volatile sig_atomic_t entered = 0;
+
+  if (size != 0) {
+    backtrace_symbols_fd(stack, size, fd);
+    if (symbolize_crash && entered == 0) {
+      entered = 1;
+      symbolize_backtrace(stack, size, fd);
+      entered = 0;
+    }
+  }
+#else
+  const char msg[] = "No stack trace available on this OS :(\n";
+
+  if (write(fd, msg, sizeof(msg) - 1) != sizeof(msg) - 1) {
+    /* sorry GCC */
+  }
+#endif
+}

src/htsbacktrace.h

@@ -0,0 +1,45 @@
+/* ------------------------------------------------------------ */
+/*
+HTTrack Website Copier, Offline Browser for Windows and Unix
+Copyright (C) 1998 Xavier Roche and other contributors
+
+SPDX-License-Identifier: GPL-3.0-or-later
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program. If not, see <http://www.gnu.org/licenses/>.
+
+Ethical use: we kindly ask that you NOT use this software to harvest email
+addresses or to collect any other private information about people. Doing so
+would dishonor our work and waste the many hours we have spent on it.
+
+Please visit our Website: http://www.httrack.com
+*/
+
+/* ------------------------------------------------------------ */
+/* File: crash backtrace printer                                 */
+/* Author: Xavier Roche                                          */
+/* ------------------------------------------------------------ */
+
+#ifndef HTSBACKTRACE_DEFH
+#define HTSBACKTRACE_DEFH
+
+/* Sample HTTRACK_NO_SYMBOLIZE before any crash: getenv() is not signal-safe.
+   Call once, from the process that installs the fatal-signal handlers. */
+void hts_backtrace_init(void);
+
+/* Write the calling thread's stack to fd, callable from a fatal signal handler:
+   raw frames first, then whatever an external symbolizer can name. Allocates
+   nothing; prints a one-line notice where the OS has no backtrace(). */
+void hts_print_backtrace(int fd);
+
+#endif

src/htscache.c

@@ -1441,7 +1441,7 @@ int cache_brstr(char *adr, char *s, size_t s_size) {
 
 /* binput bounded to a NUL-terminated buffer: refuse to start a read at or
    past `end`, so a prior over-advance can't walk a cache-index parse OOB. */
-int cache_binput(char *adr, const char *end, char *s, int max) {
+int cache_binput(const char *adr, const char *end, char *s, int max) {
   if (adr >= end) {
     s[0] = '\0';
     return 0;

src/htscache.h

@@ -93,7 +93,7 @@ void cache_rstr(FILE *fp, char *s, size_t s_size);
 char *cache_rstr_addr(FILE * fp);
 int cache_brstr(char *adr, char *s, size_t s_size);
 /* binput over a NUL-terminated buffer, bounded: no read starts at/past end. */
-int cache_binput(char *adr, const char *end, char *s, int max);
+int cache_binput(const char *adr, const char *end, char *s, int max);
 int cache_brint(char *adr, int *i);
 void cache_rint(FILE * fp, int *i);
 void cache_rLLint(FILE * fp, LLint * i);

src/htscmdline.c

@@ -0,0 +1,95 @@
+/* ------------------------------------------------------------ */
+/*
+HTTrack Website Copier, Offline Browser for Windows and Unix
+Copyright (C) 1998 Xavier Roche and other contributors
+
+SPDX-License-Identifier: GPL-3.0-or-later
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program. If not, see <http://www.gnu.org/licenses/>.
+
+Ethical use: we kindly ask that you NOT use this software to harvest email
+addresses or to collect any other private information about people. Doing so
+would dishonor our work and waste the many hours we have spent on it.
+
+Please visit our Website: http://www.httrack.com
+*/
+
+/* ------------------------------------------------------------ */
+/* File: command line splitter, shared by the engine and         */
+/*       htsserver                                               */
+/* Author: Xavier Roche                                          */
+/* ------------------------------------------------------------ */
+
+#include "htscmdline.h"
+
+#include "htssafe.h"
+
+#include <limits.h>
+#include <stdint.h>
+
+char **hts_split_cmdline(char *cmd, int *nargs) {
+  size_t nsep = 0;
+  size_t capacity;
+  size_t r;
+  size_t w;
+  int argc = 0;
+  hts_boolean quoted = HTS_FALSE;
+  char **argv;
+
+  *nargs = 0;
+
+  /* fold the other separators, so counting them sizes the vector exactly */
+  for (r = 0; cmd[r] != '\0'; r++) {
+    if (cmd[r] == '\t' || cmd[r] == '\r' || cmd[r] == '\n') {
+      cmd[r] = ' ';
+    }
+    if (cmd[r] == ' ') {
+      nsep++;
+    }
+  }
+
+  /* at most one argument per separator, plus the leading one and the NULL */
+  if (nsep > (size_t) INT_MAX - 1 || nsep > SIZE_MAX / sizeof(char *) - 2) {
+    return NULL;
+  }
+  capacity = nsep + 2;
+  argv = (char **) malloct(capacity * sizeof(char *));
+  if (argv == NULL) {
+    return NULL;
+  }
+
+  argv[argc++] = cmd;
+  for (r = 0, w = 0; cmd[r] != '\0';) {
+    if (quoted && cmd[r] == '\\' &&
+        (cmd[r + 1] == '\\' || cmd[r + 1] == '\"')) {
+      r++;
+      cmd[w++] = cmd[r++];
+    } else if (cmd[r] == '\"') {
+      quoted = !quoted;
+      cmd[w++] = cmd[r++];
+    } else if (cmd[r] == ' ' && !quoted) {
+      cmd[w++] = '\0';
+      assertf((size_t) argc < capacity - 1); /* the last slot holds the NULL */
+      argv[argc++] = cmd + w;
+      r++;
+    } else {
+      cmd[w++] = cmd[r++];
+    }
+  }
+  cmd[w] = '\0';
+  argv[argc] = NULL; /* callers may rely on argv[argc] == NULL */
+
+  *nargs = argc;
+  return argv;
+}

src/htscmdline.h

@@ -0,0 +1,45 @@
+/* ------------------------------------------------------------ */
+/*
+HTTrack Website Copier, Offline Browser for Windows and Unix
+Copyright (C) 1998 Xavier Roche and other contributors
+
+SPDX-License-Identifier: GPL-3.0-or-later
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program. If not, see <http://www.gnu.org/licenses/>.
+
+Ethical use: we kindly ask that you NOT use this software to harvest email
+addresses or to collect any other private information about people. Doing so
+would dishonor our work and waste the many hours we have spent on it.
+
+Please visit our Website: http://www.httrack.com
+*/
+
+/* ------------------------------------------------------------ */
+/* File: command line splitter, shared by the engine and         */
+/*       htsserver                                               */
+/* Author: Xavier Roche                                          */
+/* ------------------------------------------------------------ */
+
+#ifndef HTSCMDLINE_DEFH
+#define HTSCMDLINE_DEFH
+
+#include "htsglobal.h"
+
+/* Split "cmd" in place into a NULL-terminated argv vector of *nargs entries,
+   argv[0] being the program name and quotes left for the engine to strip.
+   Returns a malloct'ed vector of pointers into cmd (freet the vector, never its
+   entries), or NULL when it cannot be sized or allocated. */
+char **hts_split_cmdline(char *cmd, int *nargs);
+
+#endif

src/htscore.c

@@ -447,13 +447,22 @@ void hts_finish_makeindex(httrackp *opt, int *makeindex_done,
                           const char *fil) {
   if (!*makeindex_done) {
     if (*makeindex_fp) {
-      char BIGSTK tempo[1024];
+      /* sized off link_escaped below: at the old flat 1024 a long first link
+         produced a redirect to a clipped URL */
+      char BIGSTK tempo[HTS_URLMAXSIZE * 2 + 64];
       if (makeindex_links == 1) {
         char BIGSTK link_escaped[HTS_URLMAXSIZE * 2];
         escape_uri_utf(makeindex_firstlink, link_escaped, sizeof(link_escaped));
-        snprintf(tempo, sizeof(tempo),
-                 "<meta HTTP-EQUIV=\"Refresh\" CONTENT=\"0; URL=%s\">" CRLF,
-                 link_escaped);
+        /* no redirect beats one pointing at a clipped URL */
+        if (!sprintfbuff(
+                tempo,
+                "<meta HTTP-EQUIV=\"Refresh\" CONTENT=\"0; URL=%s\">" CRLF,
+                link_escaped)) {
+          hts_log_print(opt, LOG_WARNING,
+                        "index redirect omitted: first link too long (%s)",
+                        makeindex_firstlink);
+          tempo[0] = '\0';
+        }
       } else
         tempo[0] = '\0';
       hts_template_format(*makeindex_fp, template_footer,

src/htsftp.c

@@ -251,7 +251,7 @@ int run_launch_ftp(FTPDownloadStruct * pStruct) {
       // folding a nonsense port into 1..65535 fetches one the link never named;
       // an empty "host:" just means the default (#614)
       if (a[1] != '\0' && !hts_parse_url_port(a + 1, &port)) {
-        snprintf(back->r.msg, sizeof(back->r.msg), "Invalid port: %s", a + 1);
+        htsblk_failf(&back->r, "Invalid port: %s", a + 1);
         back->r.statuscode = STATUSCODE_INVALID; // permanent, unlike a DNS miss
         _HALT_FTP return 0;
       }
@@ -262,8 +262,7 @@ int run_launch_ftp(FTPDownloadStruct * pStruct) {
     // récupérer adresse résolue
     strcpybuff(back->info, "host name");
     if (hts_dns_resolve2(opt, _adr, &server, &error) == NULL) {
-      snprintf(back->r.msg, sizeof(back->r.msg),
-               "Unable to get server's address: %s", error);
+      htsblk_failf(&back->r, "Unable to get server's address: %s", error);
       back->r.statuscode = STATUSCODE_NON_FATAL;
       _HALT_FTP return 0;
     }
@@ -332,18 +331,15 @@ int run_launch_ftp(FTPDownloadStruct * pStruct) {
             }
 
           } else {
-            snprintf(back->r.msg, sizeof(back->r.msg), "Bad password: %s",
-                     linejmp(line));
+            htsblk_failf(&back->r, "Bad password: %s", linejmp(line));
             back->r.statuscode = STATUSCODE_INVALID;
           }
         } else {
-          snprintf(back->r.msg, sizeof(back->r.msg), "Bad user name: %s",
-                   linejmp(line));
+          htsblk_failf(&back->r, "Bad user name: %s", linejmp(line));
           back->r.statuscode = STATUSCODE_INVALID;
         }
       } else {
-        snprintf(back->r.msg, sizeof(back->r.msg), "Connection refused: %s",
-                 linejmp(line));
+        htsblk_failf(&back->r, "Connection refused: %s", linejmp(line));
         back->r.statuscode = STATUSCODE_INVALID;
       }
 
@@ -410,8 +406,7 @@ int run_launch_ftp(FTPDownloadStruct * pStruct) {
             }
             // -- fin analyse de l'adresse IP et du port --
           } else {
-            snprintf(back->r.msg, sizeof(back->r.msg), "PASV incorrect: %s",
-                     linejmp(line));
+            htsblk_failf(&back->r, "PASV incorrect: %s", linejmp(line));
             back->r.statuscode = STATUSCODE_INVALID;
           }                     // sinon on est prêts
         } else {
@@ -442,13 +437,11 @@ int run_launch_ftp(FTPDownloadStruct * pStruct) {
                 }
               }
             } else {
-              snprintf(back->r.msg, sizeof(back->r.msg), "EPSV incorrect: %s",
-                       linejmp(line));
+              htsblk_failf(&back->r, "EPSV incorrect: %s", linejmp(line));
               back->r.statuscode = STATUSCODE_INVALID;
             }
           } else {
-            snprintf(back->r.msg, sizeof(back->r.msg), "PASV/EPSV error: %s",
-                     linejmp(line));
+            htsblk_failf(&back->r, "PASV/EPSV error: %s", linejmp(line));
             back->r.statuscode = STATUSCODE_INVALID;
           }                     // sinon on est prêts
         }
@@ -554,8 +547,8 @@ int run_launch_ftp(FTPDownloadStruct * pStruct) {
                   deletesoc(soc_dat);
                   soc_dat = INVALID_SOCKET;
                   //
-                  snprintf(back->r.msg, sizeof(back->r.msg),
-                           "RETR command error: %s", linejmp(line));
+                  htsblk_failf(&back->r, "RETR command error: %s",
+                               linejmp(line));
                   back->r.statuscode = STATUSCODE_INVALID;
                 }               // sinon on est prêts
               } else {
@@ -573,13 +566,12 @@ int run_launch_ftp(FTPDownloadStruct * pStruct) {
               back->r.statuscode = STATUSCODE_INVALID;
             }                   // sinon on est prêts
           } else {
-            snprintf(back->r.msg, sizeof(back->r.msg),
-                     "Unable to resolve IP %s: %s", adr_ip, error);
+            htsblk_failf(&back->r, "Unable to resolve IP %s: %s", adr_ip,
+                         error);
             back->r.statuscode = STATUSCODE_INVALID;
           }                     // sinon on est prêts
         } else {
-          snprintf(back->r.msg, sizeof(back->r.msg), "PASV incorrect: %s",
-                   linejmp(line));
+          htsblk_failf(&back->r, "PASV incorrect: %s", linejmp(line));
           back->r.statuscode = STATUSCODE_INVALID;
         }                       // sinon on est prêts
 #else
@@ -603,13 +595,11 @@ int run_launch_ftp(FTPDownloadStruct * pStruct) {
                 back->r.statuscode = STATUSCODE_INVALID;
               }
             } else {
-              snprintf(back->r.msg, sizeof(back->r.msg),
-                       "RETR command error: %s", linejmp(line));
+              htsblk_failf(&back->r, "RETR command error: %s", linejmp(line));
               back->r.statuscode = STATUSCODE_INVALID;
             }
           } else {
-            snprintf(back->r.msg, sizeof(back->r.msg), "PORT command error: %s",
-                     linejmp(line));
+            htsblk_failf(&back->r, "PORT command error: %s", linejmp(line));
             back->r.statuscode = STATUSCODE_INVALID;
           }
 #ifdef _WIN32
@@ -652,8 +642,7 @@ int run_launch_ftp(FTPDownloadStruct * pStruct) {
                 len = 0;        // fin
                 break;
               case 0:
-                snprintf(back->r.msg, sizeof(back->r.msg), "Time out (%d)",
-                         timeout);
+                htsblk_failf(&back->r, "Time out (%d)", timeout);
                 back->r.statuscode = STATUSCODE_INVALID;
                 len = 0;        // fin
                 break;
@@ -716,8 +705,7 @@ int run_launch_ftp(FTPDownloadStruct * pStruct) {
                 strcpybuff(back->r.msg, "OK");
                 back->r.statuscode = HTTP_OK;
               } else {
-                snprintf(back->r.msg, sizeof(back->r.msg), "RETR incorrect: %s",
-                         linejmp(line));
+                htsblk_failf(&back->r, "RETR incorrect: %s", linejmp(line));
                 back->r.statuscode = STATUSCODE_INVALID;
               }
             } else {

src/htsglobal.h

@@ -72,7 +72,8 @@ Please visit our Website: http://www.httrack.com
    HTS_UNUSED: suppress unused-symbol warnings. HTS_STATIC: an unused-safe
    static. HTS_PRINTF_FUN(fmt, arg): mark a printf-like function so the
    compiler type-checks the format string at argument index fmt against the
-   varargs starting at arg. */
+   varargs starting at arg. HTS_CHECK_RESULT: the return value carries the only
+   error signal, so dropping it is a bug; a (void) cast does not silence it. */
 #ifndef HTS_UNUSED
 #ifdef __GNUC__
 #define HTS_UNUSED __attribute__((unused))
@@ -80,10 +81,13 @@ Please visit our Website: http://www.httrack.com
 #define HTS_STATIC static __attribute__((unused))
 
 #define HTS_PRINTF_FUN(fmt, arg) __attribute__((format(printf, fmt, arg)))
+
+#define HTS_CHECK_RESULT __attribute__((warn_unused_result))
 #else
 #define HTS_UNUSED
 #define HTS_STATIC static
 #define HTS_PRINTF_FUN(fmt, arg)
+#define HTS_CHECK_RESULT
 #endif
 #endif
 

src/htshelp.c

@@ -124,7 +124,9 @@ typedef struct help_wizard_buffers {
   char stropt[2048];        // options
   char stropt2[2048];       // options longues
   char strwild[2048];       // wildcards
-  char cmd[4096];
+  /* holds all four of the above plus separators: at 4096 a long answer set
+     clipped the filters off the command line */
+  char cmd[HTS_URLMAXSIZE * 2 + 3 * 2048 + 4];
   char str[256];
   char *argv[256];
 } help_wizard_buffers;
@@ -156,9 +158,7 @@ void help_wizard(httrackp * opt) {
   char *a;
 
   //
-  if (urls == NULL || mainpath == NULL || projname == NULL || stropt == NULL
-      || stropt2 == NULL || strwild == NULL || cmd == NULL || str == NULL
-      || argv == NULL) {
+  if (buffers == NULL) {
     fprintf(stderr, "* memory exhausted in %s, line %d\n", __FILE__, __LINE__);
     return;
   }
@@ -251,6 +251,7 @@ void help_wizard(httrackp * opt) {
       strcatbuff(stropt2, "--update ");
       break;
     case 0:
+      freet(buffers);
       return;
       break;
     }
@@ -309,14 +310,23 @@ void help_wizard(httrackp * opt) {
       printf("\n");
       if (strlen(stropt) == 1)
         stropt[0] = '\0';       // aucune
-      snprintf(cmd, sizeof(cmd), "%s %s %s %s", urls, stropt, stropt2, strwild);
+      /* the tail is the filter list, and cmd is split into the argv handed to
+         hts_main() below: a clipped line would silently widen the crawl */
+      if (!sprintfbuff(cmd, "%s %s %s %s", urls, stropt, stropt2, strwild)) {
+        printf("* command line too long (%d bytes max)\n",
+               (int) sizeof(cmd) - 1);
+        freet(buffers);
+        return;
+      }
       printf("---> Wizard command line: httrack %s\n\n", cmd);
       printf("Ready to launch the mirror? (Y/n) :");
       fflush(stdout);
       linput(stdin, str, 250);
       if (strnotempty(str)) {
-        if (!((str[0] == 'y') || (str[0] == 'Y')))
+        if (!((str[0] == 'y') || (str[0] == 'Y'))) {
+          freet(buffers);
           return;
+        }
       }
       printf("\n");
 
@@ -340,7 +350,7 @@ void help_wizard(httrackp * opt) {
   }
 
   /* Free buffers */
-  free(buffers);
+  freet(buffers);
 #undef urls
 #undef mainpath
 #undef projname

src/htslib.c

@@ -704,18 +704,16 @@ T_SOC http_xfopen(httrackp *opt, int mode, int treat, int waitconnect,
   /* Check for errors */
   if (soc == INVALID_SOCKET) {
     if (retour) {
-      if (retour->msg) {
-        if (!strnotempty(retour->msg)) {
+      if (!strnotempty(retour->msg)) {
 #ifdef _WIN32
-          int last_errno = WSAGetLastError();
+        int last_errno = WSAGetLastError();
 
-          sprintf(retour->msg, "Connect error: %s", strerror(last_errno));
+        sprintf(retour->msg, "Connect error: %s", strerror(last_errno));
 #else
-          int last_errno = errno;
+        int last_errno = errno;
 
-          sprintf(retour->msg, "Connect error: %s", strerror(last_errno));
+        sprintf(retour->msg, "Connect error: %s", strerror(last_errno));
 #endif
-        }
       }
     }
   }
@@ -2207,7 +2205,7 @@ T_SOC newhttp_addr(httrackp *opt, const char *_iadr, htsblk *retour, int port,
 #if DEBUG
       printf("erreur gethostbyname\n");
 #endif
-      if (retour && retour->msg) {
+      if (retour != NULL) {
 #ifdef _WIN32
         snprintf(retour->msg, sizeof(retour->msg),
                  "Unable to get server's address: %s", error);
@@ -2238,7 +2236,7 @@ T_SOC newhttp_addr(httrackp *opt, const char *_iadr, htsblk *retour, int port,
     DEBUG_W("socket()=%d\n" _(int) soc);
 #endif
     if (soc == INVALID_SOCKET) {
-      if (retour && retour->msg) {
+      if (retour != NULL) {
 #ifdef _WIN32
         int last_errno = WSAGetLastError();
 
@@ -2262,17 +2260,8 @@ T_SOC newhttp_addr(httrackp *opt, const char *_iadr, htsblk *retour, int port,
                              &bind_addr, &error) == NULL
           || bind(soc, &SOCaddr_sockaddr(bind_addr), 
                   SOCaddr_size(bind_addr)) != 0) {
-        if (retour && retour->msg) {
-#ifdef _WIN32
-          snprintf(retour->msg, sizeof(retour->msg),
-                   "Unable to bind the specificied server address: %s",
-                   error);
-#else
-          snprintf(retour->msg, sizeof(retour->msg),
-                   "Unable to bind the specificied server address: %s",
-                   error);
-#endif
-        }
+        snprintf(retour->msg, sizeof(retour->msg),
+                 "Unable to bind the specificied server address: %s", error);
         deletesoc(soc);
         return INVALID_SOCKET;
       }
@@ -2319,7 +2308,7 @@ T_SOC newhttp_addr(httrackp *opt, const char *_iadr, htsblk *retour, int port,
 #if HDEBUG
         printf("unable to connect!\n");
 #endif
-        if (retour != NULL && retour->msg) {
+        if (retour != NULL) {
 #ifdef _WIN32
           const int last_errno = WSAGetLastError();
 
@@ -2548,6 +2537,15 @@ void fil_simplifie(char *f) {
   }
 }
 
+void htsblk_failf(htsblk *r, const char *fmt, ...) {
+  va_list args;
+
+  va_start(args, fmt);
+  // deliberate clip: the reason is quoted from a remote reply
+  (void) vslprintfbuff(r->msg, sizeof(r->msg), fmt, args);
+  va_end(args);
+}
+
 // fermer liaison fichier ou socket
 void deletehttp(htsblk * r) {
 #if HTS_DEBUG_CLOSESOCK
@@ -3019,7 +3017,7 @@ int finput(T_SOC fd, char *s, int max) {
 }
 
 // Like linput, but in memory (optimized)
-int binput(char *buff, char *s, int max) {
+int binput(const char *buff, char *s, int max) {
   int count = 0;
   int destCount = 0;
 

src/htslib.h

@@ -199,6 +199,10 @@ T_SOC newhttp(httrackp * opt, const char *iadr, htsblk * retour, int port,
    etc.). */
 T_SOC newhttp_addr(httrackp *opt, const char *iadr, htsblk *retour, int port,
                    int waitconnect, int addr_index, int *addr_count);
+/* Clips the formatted failure reason into r->msg, which also round-trips
+   through the cache as X-StatusMessage. Leaves r->statuscode to the caller. */
+void htsblk_failf(htsblk *r, const char *fmt, ...) HTS_PRINTF_FUN(2, 3);
+
 HTS_INLINE void deletehttp(htsblk * r);
 HTS_INLINE int deleteaddr(htsblk * r);
 HTS_INLINE void deletesoc(T_SOC soc);
@@ -262,7 +266,7 @@ HTS_INLINE void time_rfc822_local(char *s, struct tm *A);
 
 HTS_INLINE int sendc(htsblk * r, const char *s);
 int finput(T_SOC fd, char *s, int max);
-int binput(char *buff, char *s, int max);
+int binput(const char *buff, char *s, int max);
 int linput(FILE * fp, char *s, int max);
 int linputsoc(T_SOC soc, char *s, int max);
 int linputsoc_t(T_SOC soc, char *s, int max, int timeout);

src/htsproxy.c

@@ -173,8 +173,8 @@ int http_proxy_tunnel(httrackp *opt, htsblk *retour, const char *adr,
   if (sscanf(line, "HTTP/%*d.%*d %d", &code) < 1)
     code = 0;
   if (code < 200 || code >= 300) {
-    snprintf(retour->msg, sizeof(retour->msg), "proxy CONNECT refused: %s",
-             strnotempty(line) ? line : "(no status)");
+    htsblk_failf(retour, "proxy CONNECT refused: %s",
+                 strnotempty(line) ? line : "(no status)");
     return 0;
   }
 

src/htssafe.h

@@ -33,6 +33,7 @@ Please visit our Website: http://www.httrack.com
 #ifndef HTSSAFE_DEFH
 #define HTSSAFE_DEFH
 
+#include <stdarg.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
@@ -459,6 +460,49 @@ static HTS_INLINE HTS_UNUSED const char *htsbuff_str(const htsbuff *b) {
   return b->buf;
 }
 
+/**
+ * Callers that deliberately ignore truncation use this instead of
+ * slprintfbuff(), so it is not HTS_CHECK_RESULT.
+ */
+static HTS_INLINE HTS_UNUSED HTS_PRINTF_FUN(3, 0) hts_boolean
+    vslprintfbuff(char *dest, size_t size, const char *fmt, va_list args) {
+  int ret;
+
+  assertf(dest != NULL && size != 0);
+  ret = vsnprintf(dest, size, fmt, args);
+  /* pre-C99 runtimes (msvcrt _vsnprintf) return -1 and do not terminate */
+  dest[size - 1] = '\0';
+  return ret >= 0 && (size_t) ret < size ? HTS_TRUE : HTS_FALSE;
+}
+
+/**
+ * Formatted print into dest (capacity size, NUL included), truncating to fit
+ * and always NUL-terminating. Returns HTS_TRUE if the whole output fit; the
+ * result is the only truncation signal, so it must be acted on. Unlike
+ * strcpybuff() it never aborts, so it suits text built from remote input.
+ */
+static HTS_INLINE HTS_UNUSED HTS_CHECK_RESULT HTS_PRINTF_FUN(3, 4) hts_boolean
+    slprintfbuff(char *dest, size_t size, const char *fmt, ...) {
+  va_list args;
+  hts_boolean ret;
+
+  va_start(args, fmt);
+  ret = vslprintfbuff(dest, size, fmt, args);
+  va_end(args);
+  return ret;
+}
+
+/**
+ * slprintfbuff() over the in-scope array ARR (capacity = sizeof(ARR)).
+ * On GCC/Clang a pointer is a compile error; use slprintfbuff() for those.
+ */
+#if (defined(__GNUC__) && !defined(__cplusplus))
+#define sprintfbuff(ARR, ...)                                                  \
+  slprintfbuff((ARR), sizeof(ARR) + htsbuff_must_be_array_(ARR), __VA_ARGS__)
+#else
+#define sprintfbuff(ARR, ...) slprintfbuff((ARR), sizeof(ARR), __VA_ARGS__)
+#endif
+
 /* Thin aliases over the libc allocator/memcpy (historical "t" suffix); no
    added bounds checking. freet() also NULLs the freed pointer and tolerates
    NULL. memcpybuff() despite the name is a raw memcpy: the caller owns the

src/htsselftest.c

@@ -51,6 +51,7 @@ Please visit our Website: http://www.httrack.com
 #include "htscache_selftest.h"
 #include "htsdns_selftest.h"
 #include "htscharset.h"
+#include "htscmdline.h"
 #include "htsencoding.h"
 #include "htsftp.h"
 #include "htsmd5.h"
@@ -568,6 +569,97 @@ static int string_safety_selftests(void) {
       return 1;
   }
 
+  /* sprintfbuff: truncate-and-report. Must never abort (its callers format
+     remote banners) nor write past the array, which the canary catches. */
+  {
+    struct {
+      char dst[8];
+      char canary[8];
+    } s;
+
+    const char *const big = "0123456789abcdefghijklmnopqrstuvwxyz";
+
+    /* repoison before every call, or an implementation that measures first and
+       writes nothing "passes" the truncating cases on the previous content */
+#define POISON_DST() memset(s.dst, '#', sizeof(s.dst))
+
+    memset(&s, '#', sizeof(s));
+    if (!sprintfbuff(s.dst, "%s-%d", "ab", 42) || strcmp(s.dst, "ab-42") != 0)
+      return 1;
+
+    /* exact fit: 7 characters plus the NUL */
+    POISON_DST();
+    if (!sprintfbuff(s.dst, "%s", "1234567") || strcmp(s.dst, "1234567") != 0)
+      return 1;
+
+    /* one over, then far over: truncated to the prefix, terminated, reported */
+    POISON_DST();
+    if (sprintfbuff(s.dst, "%s", "12345678") || strcmp(s.dst, "1234567") != 0)
+      return 1;
+    POISON_DST();
+    if (sprintfbuff(s.dst, "%s", big) || strcmp(s.dst, "0123456") != 0)
+      return 1;
+
+    /* explicit-capacity form, down to the degenerate size 1 */
+    {
+      char *const p = s.dst;
+
+      POISON_DST();
+      if (slprintfbuff(p, 1, "%s", "x") || p[0] != '\0')
+        return 1;
+      POISON_DST();
+      if (!slprintfbuff(p, sizeof(s.dst), "%s", "ok") || strcmp(p, "ok") != 0)
+        return 1;
+    }
+#undef POISON_DST
+
+    if (memcmp(s.canary, "########", sizeof(s.canary)) != 0)
+      return 1;
+  }
+
+  /* htsblk_failf: clips a reason quoted from a remote reply into msg[] and
+     touches nothing else in the block */
+  {
+    htsblk r;
+    char expect[sizeof(r.msg)];
+    char big[4 * sizeof(r.msg)];
+
+    /* contenttype abuts msg, so a one-past-the-end store lands in it rather
+       than in padding; checking it is this block's canary */
+#define NEIGHBOURS_INTACT() (r.contenttype[0] == '\0' && r.statuscode == 1234)
+
+    memset(&r, 0, sizeof(r));
+    r.statuscode = 1234;
+
+    memset(r.msg, '#', sizeof(r.msg));
+    htsblk_failf(&r, "PASV incorrect: %s", "220 ok");
+    if (strcmp(r.msg, "PASV incorrect: 220 ok") != 0 || !NEIGHBOURS_INTACT())
+      return 1;
+
+    /* exact fit: capacity - 1 characters plus the NUL */
+    memset(expect, 'y', sizeof(expect) - 1);
+    expect[sizeof(expect) - 1] = '\0';
+    memcpy(expect, "Bad password: ", sizeof("Bad password: ") - 1);
+    memset(r.msg, '#', sizeof(r.msg));
+    htsblk_failf(&r, "%s", expect);
+    if (strcmp(r.msg, expect) != 0 || !NEIGHBOURS_INTACT())
+      return 1;
+
+    /* far over: the expected bytes differ from the cases above, so writing
+       nothing cannot pass on the leftovers */
+    memset(big, 'z', sizeof(big) - 1);
+    big[sizeof(big) - 1] = '\0';
+    memset(expect, 'z', sizeof(expect) - 1);
+    expect[sizeof(expect) - 1] = '\0';
+    memcpy(expect, "Bad user name: ", sizeof("Bad user name: ") - 1);
+
+    memset(r.msg, '#', sizeof(r.msg));
+    htsblk_failf(&r, "Bad user name: %s", big);
+    if (strcmp(r.msg, expect) != 0 || !NEIGHBOURS_INTACT())
+      return 1;
+#undef NEIGHBOURS_INTACT
+  }
+
   /* StringCatN/StringSetLength must eval SIZE once: (n_eval++, V) leaves
      n_eval == 2 on a double-eval macro. */
   {
@@ -1126,6 +1218,128 @@ static int st_unescape_bounds(httrackp *opt, int argc, char **argv) {
   return 0;
 }
 
+// hts_split_cmdline(): the vector must grow with the argument count, and a
+// quote inside a value must not end the argument and hand -V to the parser.
+static int st_cmdlinesplit(httrackp *opt, int argc, char **argv) {
+  char line[512];
+  char **args;
+  int nargs = 0;
+
+  (void) opt;
+  (void) argc;
+  (void) argv;
+
+  // control: every separator splits, and argv[0] is the program name
+  strcpybuff(line, "httrack http://x/ --quiet\t-c8\n-O out");
+  args = hts_split_cmdline(line, &nargs);
+  assertf(args != NULL && nargs == 6);
+  assertf(args[nargs] == NULL); // callers may walk to the terminator
+  assertf(strcmp(args[0], "httrack") == 0);
+  assertf(strcmp(args[1], "http://x/") == 0);
+  assertf(strcmp(args[2], "--quiet") == 0);
+  assertf(strcmp(args[3], "-c8") == 0);
+  assertf(strcmp(args[4], "-O") == 0);
+  assertf(strcmp(args[5], "out") == 0);
+  freet(args);
+
+  // the template pads with whitespace: empty arguments are kept (the engine
+  // skips them), so the count is one per separator
+  strcpybuff(line, "httrack  --quiet");
+  args = hts_split_cmdline(line, &nargs);
+  assertf(nargs == 3 && args[1][0] == '\0');
+  assertf(strcmp(args[2], "--quiet") == 0);
+  freet(args);
+
+  // a quoted run keeps both its spaces and its quotes: the engine unquotes
+  strcpybuff(line, "httrack --user-agent \"Mozilla 5.0\" -c8");
+  args = hts_split_cmdline(line, &nargs);
+  assertf(nargs == 4);
+  assertf(strcmp(args[2], "\"Mozilla 5.0\"") == 0);
+  assertf(strcmp(args[3], "-c8") == 0);
+  freet(args);
+
+  // an escaped quote is a literal quote, not the end of the argument: the
+  // engine strips only the outer pair
+  strcpybuff(line, "httrack --user-agent \"x\\\" -V \\\"touch /tmp/pwn\" -c8");
+  args = hts_split_cmdline(line, &nargs);
+  assertf(nargs == 4);
+  assertf(strcmp(args[2], "\"x\" -V \"touch /tmp/pwn\"") == 0);
+  assertf(strcmp(args[3], "-c8") == 0);
+  freet(args);
+
+  // \\ is a literal backslash, so a Windows path survives
+  strcpybuff(line, "httrack --path \"C:\\\\dir\\\\sub\"");
+  args = hts_split_cmdline(line, &nargs);
+  assertf(nargs == 3);
+  assertf(strcmp(args[2], "\"C:\\dir\\sub\"") == 0);
+  freet(args);
+
+  // outside a quoted run a backslash is literal: the url and wildcard-filter
+  // fields, which the wizard cannot quote, read as before
+  strcpybuff(line, "httrack -*\\** +*.png");
+  args = hts_split_cmdline(line, &nargs);
+  assertf(nargs == 3);
+  assertf(strcmp(args[1], "-*\\**") == 0);
+  assertf(strcmp(args[2], "+*.png") == 0);
+  freet(args);
+
+  // a quoted run leaves slots unused, so the terminator has to be written and
+  // not inherited: size the vector from a full line first, so freeing it hands
+  // the same chunk back with stale pointers in those slots
+  strcpybuff(line, "httrack a b c d e");
+  args = hts_split_cmdline(line, &nargs);
+  assertf(nargs == 6);
+  freet(args);
+  strcpybuff(line, "httrack \"a b c d e\"");
+  args = hts_split_cmdline(line, &nargs);
+  assertf(nargs == 2);
+  assertf(args[nargs] == NULL);
+  freet(args);
+
+  // an unterminated quote protects the rest of the line, as one argument
+  strcpybuff(line, "httrack --footer \"unbalanced -V x");
+  args = hts_split_cmdline(line, &nargs);
+  assertf(nargs == 3);
+  assertf(strcmp(args[2], "\"unbalanced -V x") == 0);
+  freet(args);
+
+  // past the 1024 entries the vector used to hold: distinct arguments, so a
+  // write beyond the allocation cannot read back as the expected parse
+  {
+    const int n = 2000;
+    const size_t size = 16 * (size_t) n + 16;
+    char *big = malloct(size);
+    size_t pos = 0;
+    int i;
+
+    assertf(big != NULL);
+    pos = (size_t) snprintf(big, size, "httrack");
+    assertf(pos < size);
+    for (i = 0; i < n; i++) {
+      // snprintf returns what it wanted to write, so accumulating it blind
+      // would let the next size argument wrap
+      const int len = snprintf(big + pos, size - pos, " a%d", i);
+
+      assertf(len > 0 && (size_t) len < size - pos);
+      pos += (size_t) len;
+    }
+    args = hts_split_cmdline(big, &nargs);
+    assertf(args != NULL && nargs == n + 1);
+    assertf(args[nargs] == NULL);
+    for (i = 0; i < n; i++) {
+      char expect[16];
+
+      snprintf(expect, sizeof(expect), "a%d", i);
+      assertf(strcmp(args[i + 1], expect) == 0);
+    }
+    freet(args);
+    freet(big);
+  }
+
+  printf("cmdline-split self-test OK\n");
+  return 0;
+}
+
 static int st_hashtable(httrackp *opt, int argc, char **argv) {
   char *snum;
   unsigned long count = 0;
@@ -2488,17 +2702,20 @@ static int st_cookies(httrackp *opt, int argc, char **argv) {
     static t_cookie ck2;
     htsblk r;
     char host[600];
+    char line[64]; /* treathead NUL-cuts the header in place: never a literal */
 
     memset(&r, 0, sizeof(r));
     memset(host, 'a', sizeof(host) - 1);
     host[sizeof(host) - 1] = '\0';
     ck2.max_len = (int) sizeof(ck2.data);
     ck2.data[0] = '\0';
-    treathead(&ck2, host, "/", &r, "Set-Cookie: SID=1; path=/");
+    strcpybuff(line, "Set-Cookie: SID=1; path=/");
+    treathead(&ck2, host, "/", &r, line);
     if (strnotempty(ck2.data)) // oversize-host cookie was not dropped
       err = 1;
     /* control: a normal host still yields a cookie through treathead */
-    treathead(&ck2, dom, "/", &r, "Set-Cookie: SID=1; path=/");
+    strcpybuff(line, "Set-Cookie: SID=1; path=/");
+    treathead(&ck2, dom, "/", &r, line);
     if (strstr(ck2.data, "SID") == NULL) // guard wrongly dropped a valid cookie
       err = 1;
   }
@@ -2759,6 +2976,32 @@ static int st_makeindex(httrackp *opt, int argc, char **argv) {
   assertf(strstr(buf, "Refresh") != NULL);
   assertf(strstr(buf, "example.com") != NULL);
 
+  /* a first link whose escaped form overruns the old flat 1024-byte tempo: the
+     redirect must carry the whole URL, not a clipped prefix */
+  {
+    char BIGSTK link[HTS_URLMAXSIZE * 2];
+    char *p = link;
+
+    strcpybuff(link, "http://example.com/");
+    p += strlen(link);
+    memset(p, 'a', 1200);
+    p += 1200;
+    strcpy(p, "/end.html");
+
+    done = 0;
+    fp = fopen(path, "wb");
+    assertf(fp != NULL);
+    hts_finish_makeindex(opt, &done, &fp, 1, link, "%s%s", "", "");
+    assertf(fp == NULL);
+    fp = fopen(path, "rb");
+    assertf(fp != NULL);
+    n = fread(buf, 1, sizeof(buf) - 1, fp);
+    fclose(fp);
+    buf[n] = '\0';
+    /* the closing quote proves the URL was not clipped mid-way */
+    assertf(strstr(buf, "/end.html\">") != NULL);
+  }
+
   /* no single link: footer only, no refresh meta */
   done = 0;
   fp = fopen(path, "wb");
@@ -2988,7 +3231,7 @@ static int ae_write_packed(const char *path, int windowBits,
     deflateEnd(&strm);
     return 1;
   }
-  strm.next_in = (Bytef *) src;
+  strm.next_in = (const Bytef *) src;
   strm.avail_in = (uInt) len;
   do {
     size_t n;
@@ -4798,10 +5041,10 @@ static int st_cookieimport(httrackp *opt, int argc, char **argv) {
   char fpath[HTS_URLMAXSIZE * 2];
   char file[HTS_URLMAXSIZE * 2];
 
-  snprintf(fpath, sizeof(fpath), "%s/", dir); /* IE glob wants a trailing sep */
+  assertf(sprintfbuff(fpath, "%s/", dir)); /* IE glob wants a trailing sep */
 
   /* cookies.txt: one Netscape record (host, _, path, _, _, name, value). */
-  snprintf(file, sizeof(file), "%scookies.txt", fpath);
+  assertf(sprintfbuff(file, "%scookies.txt", fpath));
   {
     FILE *fp = FOPEN(file, "wb");
 
@@ -4811,7 +5054,7 @@ static int st_cookieimport(httrackp *opt, int argc, char **argv) {
   }
 
   /* A copied IE cookie u@v.txt: name, value, url, then 6 unused fields. */
-  snprintf(file, sizeof(file), "%su@v.txt", fpath);
+  assertf(sprintfbuff(file, "%su@v.txt", fpath));
   {
     FILE *fp = FOPEN(file, "wb");
 
@@ -4833,7 +5076,7 @@ static int st_cookieimport(httrackp *opt, int argc, char **argv) {
 #endif
 
   (void) UNLINK(file); /* u@v.txt (already gone on Windows) */
-  snprintf(file, sizeof(file), "%scookies.txt", fpath);
+  assertf(sprintfbuff(file, "%scookies.txt", fpath));
   (void) UNLINK(file);
   dir[dirlen] = '\0';
   while (strlen(dir) > base) {
@@ -4907,6 +5150,9 @@ static const struct selftest_entry {
      st_footerfmt},
     {"unescape-bounds", "", "unescapers reserve the NUL byte (no 1-byte OOB)",
      st_unescape_bounds},
+    {"cmdline-split", "",
+     "webhttrack command-line to argv split (bounds, quoting)",
+     st_cmdlinesplit},
     {"hashtable", "<count|file>", "coucal hashtable stress test", st_hashtable},
     {"strsafe", "[overflow|overflow-buff|overflow-src [str]]",
      "bounded string-op self-test", st_strsafe},

src/htsserver.c

@@ -363,6 +363,43 @@ static hts_boolean body_sid_is_valid(const char *body, const char *expected) {
   return seen;
 }
 
+/* Append c to dst as an HTML entity, or return HTS_FALSE if it needs none. */
+static hts_boolean cat_html_escaped(String *dst, char c) {
+  switch (c) {
+  case '<':
+    StringCat(*dst, "&lt;");
+    break;
+  case '>':
+    StringCat(*dst, "&gt;");
+    break;
+  case '&':
+    StringCat(*dst, "&amp;");
+    break;
+  case '\'':
+    StringCat(*dst, "&#39;");
+    break;
+  default:
+    return HTS_FALSE;
+  }
+  return HTS_TRUE;
+}
+
+/* Append the value of a double-quoted command-line argument: escaped for HTML,
+   which the browser undoes when it posts the command line back, and for the
+   argv splitter, which does not. */
+static void cat_cmdline_arg(String *output, const char *value) {
+  const char *a;
+
+  for (a = value; *a != '\0'; a++) {
+    if (*a == '\\' || *a == '\"') {
+      StringCat(*output, "\\");
+    }
+    if (!cat_html_escaped(output, *a)) {
+      StringMemcat(*output, a, 1);
+    }
+  }
+}
+
 int smallserver(T_SOC soc, char *url, char *method, char *data, char *path) {
   int timeout = 30;
   int retour = 0;
@@ -993,6 +1030,7 @@ int smallserver(T_SOC soc, char *url, char *method, char *data, char *path) {
                     int p;
                     int format = 0;
                     int listDefault = 0;
+                    hts_boolean unquoted = HTS_FALSE;
 
                     name[0] = '\0';
                     strlncatbuff(name, str, sizeof(name_), n);
@@ -1002,6 +1040,12 @@ int smallserver(T_SOC soc, char *url, char *method, char *data, char *path) {
                     } else if ((p = strfield(name, "html:"))) {
                       name += p;
                       format = 1;
+                    } else if ((p = strfield(name, "unquoted:"))) {
+                      name += p;
+                      unquoted = HTS_TRUE;
+                    } else if ((p = strfield(name, "arg:"))) {
+                      name += p;
+                      format = 5;
                     } else if ((p = strfield(name, "list:"))) {
                       name += p;
                       format = 2;
@@ -1138,8 +1182,8 @@ int smallserver(T_SOC soc, char *url, char *method, char *data, char *path) {
                        test:<if ==0>:<if ==1>:<if == 2>..
                        ztest:<if == 0 || !exist>:<if == 1>:<if == 2>..
                      */
-                    else if ((p = strfield(name, "test:"))
-                             || (p = strfield(name, "ztest:"))) {
+                    else if ((p = strfield(name, "test:")) ||
+                             (p = strfield(name, "ztest:"))) {
                       intptr_t adr = 0;
                       char *pos2;
                       int ztest = (name[0] == 'z');
@@ -1242,6 +1286,12 @@ int smallserver(T_SOC soc, char *url, char *method, char *data, char *path) {
                         }
                       }
                     }
+                    /* consumed here: it shares nothing with the list and
+                       option formats below */
+                    if (format == 5 && langstr != NULL && outputmode != -1) {
+                      cat_cmdline_arg(&output, langstr);
+                      langstr = NULL;
+                    }
                     if (langstr && outputmode != -1) {
                       switch (format) {
                       case 0:
@@ -1259,18 +1309,18 @@ int smallserver(T_SOC soc, char *url, char *method, char *data, char *path) {
                                 StringMemcat(output, &c, 1);
                               }
                               a += 2;
-                            } else if (outputmode && a[0] == '<') {
-                              StringCat(output, "&lt;");
-                            } else if (outputmode && a[0] == '>') {
-                              StringCat(output, "&gt;");
-                            } else if (outputmode && a[0] == '&') {
-                              StringCat(output, "&amp;");
-                            } else if (outputmode && a[0] == '\'') {
-                              StringCat(output, "&#39;");
+                            } else if (unquoted && a[0] == '\"') {
+                              /* the browser posts an entity back as a raw
+                                 quote, which would open a quoted run in the
+                                 argv splitter; a URI cannot hold one anyway */
+                              StringCat(output, "%22");
+                            } else if (outputmode &&
+                                       cat_html_escaped(&output, a[0])) {
+                              /* appended as an entity */
                             } else if (outputmode == 3 && a[0] == ' ') {
                               StringCat(output, "%20");
-                            } else if (outputmode >= 2
-                                       && ((unsigned char) a[0]) < 32) {
+                            } else if (outputmode >= 2 &&
+                                       ((unsigned char) a[0]) < 32) {
                               char tmp[32];
 
                               sprintf(tmp, "%%%02x", (unsigned char) a[0]);
@@ -1331,20 +1381,10 @@ int smallserver(T_SOC soc, char *url, char *method, char *data, char *path) {
                               }
                               StringClear(tmpbuff);
                               break;
-                            case '<':
-                              StringCat(tmpbuff, "&lt;");
-                              break;
-                            case '>':
-                              StringCat(tmpbuff, "&gt;");
-                              break;
-                            case '&':
-                              StringCat(tmpbuff, "&amp;");
-                              break;
-                            case '\'':
-                              StringCat(tmpbuff, "&#39;");
-                              break;
                             default:
-                              StringMemcat(tmpbuff, fstr, 1);
+                              if (!cat_html_escaped(&tmpbuff, *fstr)) {
+                                StringMemcat(tmpbuff, fstr, 1);
+                              }
                               break;
                             }
                             fstr++;

src/htstools.c

@@ -1318,19 +1318,19 @@ HTSEXT_API hts_boolean hts_findnext(find_handle find) {
   if (find) {
 #ifdef _WIN32
     if ((FindNextFileA(find->handle, &find->hdata)))
-      return 1;
+      return HTS_TRUE;
 #else
     char catbuff[CATBUFF_SIZE];
 
     memset(&(find->filestat), 0, sizeof(find->filestat));
     if ((find->dirp = readdir(find->hdir)))
-      if (find->dirp->d_name)
-        if (!STAT
-            (concat(catbuff, sizeof(catbuff), find->path, find->dirp->d_name), &find->filestat))
-          return 1;
+      if (!STAT(
+              concat(catbuff, sizeof(catbuff), find->path, find->dirp->d_name),
+              &find->filestat))
+        return HTS_TRUE;
 #endif
   }
-  return 0;
+  return HTS_FALSE;
 }
 
 HTSEXT_API int hts_findclose(find_handle find) {

src/htsweb.c

@@ -62,6 +62,7 @@ Please visit our Website: http://www.httrack.com
 #include "htsmd5.c"
 #include "md5.c"
 
+#include "htscmdline.h"
 #include "htsserver.h"
 #include "htsurlport.h"
 #include "htsweb.h"
@@ -319,10 +320,8 @@ int main(int argc, char *argv[]) {
 static int webhttrack_runmain(httrackp * opt, int argc, char **argv);
 static void back_launch_cmd(void *pP) {
   char *cmd = (char *) pP;
-  char **argv = (char **) malloct(1024 * sizeof(char *));
+  char **argv;
   int argc = 0;
-  int i = 0;
-  int g = 0;
 
   //
   httrackp *opt;
@@ -333,28 +332,19 @@ static void back_launch_cmd(void *pP) {
   commandReturnCmdl = strdup(cmd);
 
   /* split */
-  argv[0] = strdup("webhttrack");
-  argv[1] = cmd;
-  argc++;
-  i = 0;
-  while(cmd[i]) {
-    if (cmd[i] == '\t' || cmd[i] == '\r' || cmd[i] == '\n') {
-      cmd[i] = ' ';
-    }
-    i++;
-  }
-  i = 0;
-  while(cmd[i]) {
-    if (cmd[i] == '\"')
-      g = !g;
-    if (cmd[i] == ' ') {
-      if (!g) {
-        cmd[i] = '\0';
-        argv[argc++] = cmd + i + 1;
-      }
-    }
-    i++;
+  argv = hts_split_cmdline(cmd, &argc);
+  if (argv == NULL) {
+    if (commandReturnMsg)
+      free(commandReturnMsg);
+    commandReturnMsg = strdup("could not parse the command line");
+    commandReturn = -1;
+    commandRunning = 0;
+    commandEnd = 1;
+    free(cmd);
+    return;
   }
+  /* drop the program name the posted command line carries */
+  argv[0] = strdupt("webhttrack");
 
   /* init */
   hts_init();
@@ -383,6 +373,7 @@ static void back_launch_cmd(void *pP) {
 
   /* free */
   free(cmd);
+  freet(argv[0]);
   freet(argv);
   return;
 }

src/htsweb.h

@@ -42,7 +42,7 @@ Please visit our Website: http://www.httrack.com
 typedef struct t_StatsBuffer {
   char name[1024];
   char file[1024];
-  char state[256];
+  char state[288];                      // a short label plus back->info[256]
   char url_sav[HTS_URLMAXSIZE * 2];     // pour cancel
   char url_adr[HTS_URLMAXSIZE * 2];
   char url_fil[HTS_URLMAXSIZE * 2];

src/httrack.c

@@ -46,6 +46,7 @@ Please visit our Website: http://www.httrack.com
 #include "httrack.h"
 #include "htslib.h"
 #include "htscharset.h" // after htslib.h: winsock2.h must precede windows.h
+#include "htsbacktrace.h"
 
 /* Static definitions */
 static int fexist(const char *s);
@@ -72,10 +73,6 @@ static int linput(FILE * fp, char *s, int max);
 #include <sys/ioctl.h>
 #endif
 #include <ctype.h>
-#if (defined(__linux) && defined(HAVE_EXECINFO_H))
-#include <execinfo.h>
-#define USES_BACKTRACE
-#endif
 /* END specific definitions */
 
 static void __cdecl htsshow_init(t_hts_callbackarg * carg);
@@ -880,21 +877,6 @@ static void sig_doback(int blind) {     // mettre en backing
 #undef FD_ERR
 #define FD_ERR 2
 
-static void print_backtrace(void) {
-#ifdef USES_BACKTRACE
-  void *stack[256];
-  const int size = backtrace(stack, sizeof(stack)/sizeof(stack[0]));
-  if (size != 0) {
-    backtrace_symbols_fd(stack, size, FD_ERR);
-  }
-#else
-  const char msg[] = "No stack trace available on this OS :(\n";
-  if (write(FD_ERR, msg, sizeof(msg) - 1) != sizeof(msg) - 1) {
-    /* sorry GCC */
-  }
-#endif
-}
-
 static size_t print_num(char *buffer, int num) {
   size_t i, j;
   if (num < 0) {
@@ -928,7 +910,7 @@ static void sig_fatal(int code) {
   size += print_num(&buffer[size], code);
   buffer[size++] = '\n';
   (void) (write(FD_ERR, buffer, size) == size);
-  print_backtrace();
+  hts_print_backtrace(FD_ERR);
   (void) (write(FD_ERR, msgreport, sizeof(msgreport) - 1)
     == sizeof(msgreport) - 1);
   abort();
@@ -951,6 +933,7 @@ static void sig_leave(int code) {
 }
 
 static void signal_handlers(void) {
+  hts_backtrace_init();
 #ifdef _WIN32
   signal(SIGINT, sig_leave);    // ^C
   signal(SIGTERM, sig_finish);  // kill <process>

src/httrack.h

@@ -44,7 +44,7 @@ typedef struct t_StatsBuffer t_StatsBuffer;
 struct t_StatsBuffer {
   char name[1024];
   char file[1024];
-  char state[256];
+  char state[288]; // a short label plus back->info[256]
   char BIGSTK url_sav[HTS_URLMAXSIZE * 2];      // pour cancel
   char BIGSTK url_adr[HTS_URLMAXSIZE * 2];
   char BIGSTK url_fil[HTS_URLMAXSIZE * 2];

src/httrack.vcxproj

@@ -100,6 +100,7 @@
 
   <ItemGroup>
     <ClCompile Include="httrack.c" />
+    <ClCompile Include="htsbacktrace.c" />
   </ItemGroup>
 
   <!-- Pulls in libhttrack.lib and builds it first. -->

src/libhttrack.vcxproj

@@ -59,9 +59,10 @@
   <ItemDefinitionGroup>
     <ClCompile>
       <!-- LIBHTTRACK_EXPORTS turns HTSEXT_API into __declspec(dllexport); ZLIB_DLL
-           imports zlib from its DLL. HTS_USEBROTLI/HTS_USEZSTD enable the br and
-           zstd content codings. Windows 7 floor, matching WinHTTrack. -->
-      <PreprocessorDefinitions>WIN32;_WINDOWS;_MBCS;_USRDLL;LIBHTTRACK_EXPORTS;ZLIB_DLL;HTS_USEBROTLI=1;HTS_USEZSTD=1;WINVER=0x0601;_WIN32_WINNT=0x0601;_CRT_SECURE_NO_WARNINGS;_CRT_NONSTDC_NO_DEPRECATE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+           imports zlib from its DLL, ZLIB_CONST makes its next_in const as the
+           autotools build does. HTS_USEBROTLI/HTS_USEZSTD enable the br and zstd
+           content codings. Windows 7 floor, matching WinHTTrack. -->
+      <PreprocessorDefinitions>WIN32;_WINDOWS;_MBCS;_USRDLL;LIBHTTRACK_EXPORTS;ZLIB_DLL;ZLIB_CONST;HTS_USEBROTLI=1;HTS_USEZSTD=1;WINVER=0x0601;_WIN32_WINNT=0x0601;_CRT_SECURE_NO_WARNINGS;_CRT_NONSTDC_NO_DEPRECATE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <AdditionalIncludeDirectories>$(MSBuildThisFileDirectory);$(MSBuildThisFileDirectory)coucal;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <WarningLevel>Level3</WarningLevel>
       <MultiProcessorCompilation>true</MultiProcessorCompilation>
@@ -121,6 +122,7 @@
     <ClCompile Include="htshelp.c" />
     <ClCompile Include="htsindex.c" />
     <ClCompile Include="htslib.c" />
+    <ClCompile Include="htscmdline.c" />
     <ClCompile Include="htsurlport.c" />
     <ClCompile Include="htsmd5.c" />
     <ClCompile Include="htsmodules.c" />

src/proxy/proxytrack.c

@@ -688,7 +688,7 @@ static PT_Element proxytrack_process_DAV_Request(PT_Indexes indexes,
     PT_Element elt = PT_ElementNew();
 
     elt->statuscode = 405;
-    strcpy(elt->msg, "Method Not Allowed");
+    strcpybuff(elt->msg, "Method Not Allowed");
     return elt;
   }
 
@@ -771,7 +771,7 @@ static PT_Element proxytrack_process_DAV_Request(PT_Indexes indexes,
                   PT_ReadIndex(indexes, StringBuff(itemUrl) + 1, FETCH_HEADERS);
                 if (file != NULL && file->statuscode == HTTP_OK) {
                   size = file->size;
-                  if (file->lastmodified) {
+                  if (file->lastmodified[0] != '\0') {
                     timestamp = get_time_rfc822(file->lastmodified);
                   }
                   if (timestamp == (time_t) 0) {
@@ -785,7 +785,7 @@ static PT_Element proxytrack_process_DAV_Request(PT_Indexes indexes,
                     }
                     timestamp = timestampRep;
                   }
-                  if (file->contenttype) {
+                  if (file->contenttype[0] != '\0') {
                     mimeType = file->contenttype;
                   }
                 }
@@ -822,7 +822,7 @@ static PT_Element proxytrack_process_DAV_Request(PT_Indexes indexes,
     elt->statuscode = 207;      /* Multi-Status */
     strcpy(elt->charset, "utf-8");
     strcpy(elt->contenttype, "text/xml");
-    strcpy(elt->msg, "Multi-Status");
+    strcpybuff(elt->msg, "Multi-Status");
     StringFree(response);
 
     fprintf(stderr, "RESPONSE:\n%s\n", elt->adr);
@@ -879,7 +879,7 @@ static PT_Element proxytrack_process_HTTP_List(PT_Indexes indexes,
     elt->statuscode = HTTP_OK;
     strcpy(elt->charset, "iso-8859-1");
     strcpy(elt->contenttype, "text/html");
-    strcpy(elt->msg, "OK");
+    strcpybuff(elt->msg, "OK");
     StringFree(html);
     return elt;
   }

src/proxy/store.c

@@ -407,7 +407,7 @@ PT_Element PT_Index_HTML_BuildRootInfo(PT_Indexes indexes) {
     elt->statuscode = HTTP_OK;
     strcpy(elt->charset, "iso-8859-1");
     strcpy(elt->contenttype, "text/html");
-    strcpy(elt->msg, "OK");
+    strcpybuff(elt->msg, "OK");
     StringFree(html);
     return elt;
   }
@@ -579,9 +579,10 @@ PT_Index PT_LoadCache(const char *filename) {
         if (chain != NULL) {
           const char *scheme = link_has_authority(chain->name) ? "" : "http://";
 
-          snprintf(index->slots.common.startUrl,
-                   sizeof(index->slots.common.startUrl), "%s%s", scheme,
-                   (const char *) chain->name);
+          /* dropped rather than truncated: empty already reads as "unset" */
+          if (!sprintfbuff(index->slots.common.startUrl, "%s%s", scheme,
+                           (const char *) chain->name))
+            index->slots.common.startUrl[0] = '\0';
         }
       }
     }
@@ -827,6 +828,18 @@ PT_Element PT_ElementNew(void) {
   return r;
 }
 
+/* ProxyTrack's htsblk_failf(): a clipped, diagnostic-only failure reason. */
+static void PT_Element_failf(PT_Element r, const char *fmt, ...)
+    HTS_PRINTF_FUN(2, 3);
+
+static void PT_Element_failf(PT_Element r, const char *fmt, ...) {
+  va_list args;
+
+  va_start(args, fmt);
+  (void) vslprintfbuff(r->msg, sizeof(r->msg), fmt, args);
+  va_end(args);
+}
+
 PT_Element PT_ReadCache(PT_Index index, const char *url, int flags) {
   if (index != NULL && SAFE_INDEX(index)) {
     return _IndexFuncts[index->type].PT_ReadCache(index, url, flags);
@@ -972,9 +985,12 @@ int PT_LoadCache__New(PT_Index index_, const char *filename) {
                     const char *scheme =
                         link_has_authority(filenameIndex) ? "" : "http://";
 
-                    firstSeen = 1;
-                    snprintf(index->startUrl, sizeof(index->startUrl), "%s%s",
-                             scheme, filenameIndex);
+                    /* dropped rather than truncated; try the next entry */
+                    if (sprintfbuff(index->startUrl, "%s%s", scheme,
+                                    filenameIndex))
+                      firstSeen = 1;
+                    else
+                      index->startUrl[0] = '\0';
                   }
                 }
               } else {
@@ -1135,8 +1151,9 @@ static PT_Element PT_ReadCache__New_u(PT_Index index_, const char *url,
                   snprintf(previous_save, sizeof(previous_save), "%s%s",
                            index->path, previous_save_ + index->fixedPath);
                 } else {
-                  snprintf(r->msg, sizeof(r->msg), "Bogus fixePath prefix for %s (prefixLen=%d)",
-                          previous_save_, (int) index->fixedPath);
+                  PT_Element_failf(
+                      r, "Bogus fixePath prefix for %s (prefixLen=%d)",
+                      previous_save_, (int) index->fixedPath);
                   r->statuscode = STATUSCODE_INVALID;
                 }
               } else {
@@ -1155,7 +1172,7 @@ static PT_Element PT_ReadCache__New_u(PT_Index index_, const char *url,
             // Peut-on stocker le fichier directement sur disque?
             if (ok) {
               if (r->msg[0] == '\0') {
-                strcpy(r->msg, "Cache Read Error : Unexpected error");
+                strcpybuff(r->msg, "Cache Read Error : Unexpected error");
               }
             } else {            // lire en mémoire
 
@@ -1173,24 +1190,27 @@ static PT_Element PT_ReadCache__New_u(PT_Index index_, const char *url,
                           int last_errno = errno;
 
                           r->statuscode = STATUSCODE_INVALID;
-                          sprintf(r->msg, "Read error in cache disk data: %s",
-                                  strerror(last_errno));
+                          PT_Element_failf(r,
+                                           "Read error in cache disk data: %s",
+                                           strerror(last_errno));
                         }
                         r->adr[r->size] = '\0';
                       } else {
                         r->statuscode = STATUSCODE_INVALID;
-                        strcpy(r->msg,
-                               "Read error (memory exhausted) from cache");
+                        strcpybuff(r->msg,
+                                   "Read error (memory exhausted) from cache");
                       }
                       fclose(fp);
                     } else {
                       r->statuscode = STATUSCODE_INVALID;
-                      snprintf(r->msg, sizeof(r->msg), "Read error (can't open '%s') from cache",
-                              file_convert(catbuff, sizeof(catbuff), previous_save));
+                      PT_Element_failf(
+                          r, "Read error (can't open '%s') from cache",
+                          file_convert(catbuff, sizeof(catbuff),
+                                       previous_save));
                     }
                   } else {
                     r->statuscode = STATUSCODE_INVALID;
-                    strcpy(r->msg, "Cached file name is invalid");
+                    strcpybuff(r->msg, "Cached file name is invalid");
                   }
                 }
               } else {
@@ -1202,12 +1222,12 @@ static PT_Element PT_ReadCache__New_u(PT_Index index_, const char *url,
                       free(r->adr);
                       r->adr = NULL;
                       r->statuscode = STATUSCODE_INVALID;
-                      strcpy(r->msg, "Cache Read Error : Read Data");
+                      strcpybuff(r->msg, "Cache Read Error : Read Data");
                     } else
                       *(r->adr + r->size) = '\0';
                   } else {      // erreur
                     r->statuscode = STATUSCODE_INVALID;
-                    strcpy(r->msg, "Cache Memory Error");
+                    strcpybuff(r->msg, "Cache Memory Error");
                   }
                 }
               }
@@ -1215,21 +1235,21 @@ static PT_Element PT_ReadCache__New_u(PT_Index index_, const char *url,
           }                     // si save==null, ne rien charger (juste en tête)
         } else {
           r->statuscode = STATUSCODE_INVALID;
-          strcpy(r->msg, "Cache Read Error : Read Header Data");
+          strcpybuff(r->msg, "Cache Read Error : Read Header Data");
         }
         unzCloseCurrentFile(index->zFile);
       } else {
         r->statuscode = STATUSCODE_INVALID;
-        strcpy(r->msg, "Cache Read Error : Open File");
+        strcpybuff(r->msg, "Cache Read Error : Open File");
       }
 
     } else {
       r->statuscode = STATUSCODE_INVALID;
-      strcpy(r->msg, "Cache Read Error : Bad Offset");
+      strcpybuff(r->msg, "Cache Read Error : Bad Offset");
     }
   } else {
     r->statuscode = STATUSCODE_INVALID;
-    strcpy(r->msg, "File Cache Entry Not Found");
+    strcpybuff(r->msg, "File Cache Entry Not Found");
   }
   if (r->location[0] != '\0') {
     r->location = strdup(r->location);
@@ -1570,9 +1590,11 @@ static int PT_LoadCache__Old(PT_Index index_, const char *filename) {
                   const char *scheme =
                       link_has_authority(line) ? "" : "http://";
 
-                  firstSeen = 1;
-                  snprintf(index->startUrl, sizeof(index->startUrl), "%s%s",
-                           scheme, line);
+                  /* dropped rather than truncated; try the next entry */
+                  if (sprintfbuff(index->startUrl, "%s%s", scheme, line))
+                    firstSeen = 1;
+                  else
+                    index->startUrl[0] = '\0';
                 }
               }
 
@@ -1793,8 +1815,9 @@ static PT_Element PT_ReadCache__Old_u(PT_Index index_, const char *url,
                 snprintf(previous_save, sizeof(previous_save), "%s%s",
                          index->path, previous_save_ + index->fixedPath);
               } else {
-                snprintf(r->msg, sizeof(r->msg), "Bogus fixePath prefix for %s (prefixLen=%d)",
-                        previous_save_, (int) index->fixedPath);
+                PT_Element_failf(r,
+                                 "Bogus fixePath prefix for %s (prefixLen=%d)",
+                                 previous_save_, (int) index->fixedPath);
                 r->statuscode = STATUSCODE_INVALID;
               }
             } else {
@@ -1820,17 +1843,18 @@ static PT_Element PT_ReadCache__Old_u(PT_Index index_, const char *url,
                 if (r->adr != NULL) {
                   if (r->size > 0 && fread(r->adr, 1, r->size, fp) != r->size) {
                     r->statuscode = STATUSCODE_INVALID;
-                    strcpy(r->msg, "Read error in cache disk data");
+                    strcpybuff(r->msg, "Read error in cache disk data");
                   }
                   r->adr[r->size] = '\0';
                 } else {
                   r->statuscode = STATUSCODE_INVALID;
-                  strcpy(r->msg, "Read error (memory exhausted) from cache");
+                  strcpybuff(r->msg,
+                             "Read error (memory exhausted) from cache");
                 }
                 fclose(fp);
               } else {
                 r->statuscode = STATUSCODE_INVALID;
-                strcpy(r->msg, "Previous cache file not found (2)");
+                strcpybuff(r->msg, "Previous cache file not found (2)");
               }
             }
           } else {
@@ -1842,30 +1866,30 @@ static PT_Element PT_ReadCache__Old_u(PT_Index index_, const char *url,
                   free(r->adr);
                   r->adr = NULL;
                   r->statuscode = STATUSCODE_INVALID;
-                  strcpy(r->msg, "Cache Read Error : Read Data");
+                  strcpybuff(r->msg, "Cache Read Error : Read Data");
                 } else
                   r->adr[r->size] = '\0';
               } else {          // erreur
                 r->statuscode = STATUSCODE_INVALID;
-                strcpy(r->msg, "Cache Memory Error");
+                strcpybuff(r->msg, "Cache Memory Error");
               }
             }
           }
         } else {
           r->statuscode = STATUSCODE_INVALID;
-          strcpy(r->msg, "Cache Read Error : Bad Data");
+          strcpybuff(r->msg, "Cache Read Error : Bad Data");
         }
       } else {                  // erreur
         r->statuscode = STATUSCODE_INVALID;
-        strcpy(r->msg, "Cache Read Error : Read Header");
+        strcpybuff(r->msg, "Cache Read Error : Read Header");
       }
     } else {
       r->statuscode = STATUSCODE_INVALID;
-      strcpy(r->msg, "Cache Read Error : Seek Failed");
+      strcpybuff(r->msg, "Cache Read Error : Seek Failed");
     }
   } else {
     r->statuscode = STATUSCODE_INVALID;
-    strcpy(r->msg, "File Cache Entry Not Found");
+    strcpybuff(r->msg, "File Cache Entry Not Found");
   }
   if (r->location[0] != '\0') {
     r->location = strdup(r->location);
@@ -2246,7 +2270,7 @@ static PT_Element PT_ReadCache__Arc_u(PT_Index index_, const char *url,
                 fetchSize = dataLength - metaSize;
               } else if (fetchSize > dataLength - metaSize) {
                 r->statuscode = STATUSCODE_INVALID;
-                strcpy(r->msg, "Cache Read Error : Truncated Data");
+                strcpybuff(r->msg, "Cache Read Error : Truncated Data");
               }
               r->size = 0;
               if (r->statuscode != STATUSCODE_INVALID) {
@@ -2259,12 +2283,13 @@ static PT_Element PT_ReadCache__Arc_u(PT_Index index_, const char *url,
                     int last_errno = errno;
 
                     r->statuscode = STATUSCODE_INVALID;
-                    sprintf(r->msg, "Read error in cache disk data: %s",
-                            strerror(last_errno));
+                    PT_Element_failf(r, "Read error in cache disk data: %s",
+                                     strerror(last_errno));
                   }
                 } else {
                   r->statuscode = STATUSCODE_INVALID;
-                  strcpy(r->msg, "Read error (memory exhausted) from cache");
+                  strcpybuff(r->msg,
+                             "Read error (memory exhausted) from cache");
                 }
               }
             }
@@ -2272,21 +2297,21 @@ static PT_Element PT_ReadCache__Arc_u(PT_Index index_, const char *url,
 
         } else {
           r->statuscode = STATUSCODE_INVALID;
-          strcpy(r->msg, "Cache Read Error : Read Header Error");
+          strcpybuff(r->msg, "Cache Read Error : Read Header Error");
         }
 
       } else {
         r->statuscode = STATUSCODE_INVALID;
-        strcpy(r->msg, "Cache Read Error : Read Header Error");
+        strcpybuff(r->msg, "Cache Read Error : Read Header Error");
       }
     } else {
       r->statuscode = STATUSCODE_INVALID;
-      strcpy(r->msg, "Cache Read Error : Seek Error");
+      strcpybuff(r->msg, "Cache Read Error : Seek Error");
     }
 
   } else {
     r->statuscode = STATUSCODE_INVALID;
-    strcpy(r->msg, "File Cache Entry Not Found");
+    strcpybuff(r->msg, "File Cache Entry Not Found");
   }
   if (r->location[0] != '\0') {
     r->location = strdup(r->location);

src/webhttrack.vcxproj

@@ -97,6 +97,7 @@
   <ItemGroup>
     <ClCompile Include="htsserver.c" />
     <ClCompile Include="htsweb.c" />
+    <ClCompile Include="htscmdline.c" />
     <ClCompile Include="htsurlport.c" />
   </ItemGroup>
 

tests/01_engine-cmdline-split.test

@@ -0,0 +1,8 @@
+#!/bin/bash
+#
+
+set -euo pipefail
+
+# webhttrack posts its command line as one string: the argv split must grow past
+# 1024 arguments and keep a quote inside a value out of the option parser.
+httrack -O /dev/null -#test=cmdline-split run | grep -q "cmdline-split self-test OK"

tests/79_local-proxytrack-webdav-mime.test

@@ -0,0 +1,90 @@
+#!/bin/bash
+#
+# proxytrack's WebDAV PROPFIND fallback must behave identically whether or not
+# the cache entry supplies Content-Type and Last-Modified.
+
+set -euo pipefail
+
+: "${top_srcdir:=..}"
+# shellcheck source=tests/testlib.sh
+. "$top_srcdir/tests/testlib.sh"
+
+python=$(find_python) || {
+    echo "python3 missing, skipping"
+    exit 77
+}
+command -v curl >/dev/null 2>&1 || {
+    echo "curl missing, skipping"
+    exit 77
+}
+# First test to run proxytrack as a live server, and MSYS cannot reap a native
+# listener: the orphan wedged the whole Windows suite for 48 minutes (#595).
+if is_windows; then
+    echo "windows: cannot reap a backgrounded proxytrack, skipping"
+    exit 77
+fi
+
+dir=$(mktemp -d)
+ptpid=
+cleanup() {
+    stop_server "$ptpid"
+    rm -rf "$dir"
+}
+trap cleanup EXIT
+
+# Neither header is present, so file->contenttype and ->lastmodified stay "".
+printf 'HTTP/1.1 200 OK\r\nContent-Length: 5\r\n\r\n' >"$dir/hdr"
+printf 'hello' >"$dir/body"
+alen=$(($(wc -c <"$dir/hdr") + $(wc -c <"$dir/body")))
+{
+    printf 'filedesc://t.arc 0.0.0.0 20250101000000 text/plain 200 - - 0 t.arc 9\n'
+    printf '2 0 test\n'
+    printf '\n\n'
+    printf 'http://example.com/page.html 0.0.0.0 20250101000000 text/html 200 - - 0 t.arc %d\n' "$alen"
+    cat "$dir/hdr" "$dir/body"
+} >"$dir/in.arc"
+
+freeport() {
+    "$python" -c 'import socket; s=socket.socket(); s.bind(("127.0.0.1",0)); print(s.getsockname()[1]); s.close()'
+}
+proxyport=$(freeport)
+icpport=$(freeport)
+
+proxytrack "127.0.0.1:$proxyport" "127.0.0.1:$icpport" "$dir/in.arc" >"$dir/pt.log" 2>&1 &
+ptpid=$!
+waited=0
+until grep -qE "HTTP Proxy installed on|Unable to (initialize a temporary server|create the server)" "$dir/pt.log"; do
+    kill -0 "$ptpid" 2>/dev/null || {
+        echo "FAIL: proxytrack exited before listening"
+        cat "$dir/pt.log"
+        exit 1
+    }
+    test "$waited" -lt 50 || {
+        echo "FAIL: proxytrack never announced its listen port"
+        exit 1
+    }
+    sleep 0.1
+    waited=$((waited + 1))
+done
+grep -q "HTTP Proxy installed on" "$dir/pt.log" || {
+    echo "FAIL: proxytrack failed to bind"
+    cat "$dir/pt.log"
+    exit 1
+}
+
+# --max-time: an unbounded read here would wedge the runner rather than fail
+curl -s --max-time 30 -X PROPFIND -H "Depth: 1" \
+    "http://127.0.0.1:$proxyport/webdav/example.com/" >"$dir/resp.xml"
+
+grep -q '<getcontenttype>application/octet-stream</getcontenttype>' "$dir/resp.xml" || {
+    echo "FAIL: missing Content-Type did not fall back to application/octet-stream"
+    cat "$dir/resp.xml"
+    exit 1
+}
+grep -q '<getlastmodified>Wed, 01 Jan 2025 00:00:00 GMT</getlastmodified>' "$dir/resp.xml" || {
+    echo "FAIL: missing Last-Modified did not fall back to the index timestamp"
+    cat "$dir/resp.xml"
+    exit 1
+}
+
+echo "OK: WebDAV listing falls back correctly for an entry with no Content-Type/Last-Modified"

tests/80_engine-crash-symbolize.test

@@ -0,0 +1,97 @@
+#!/bin/bash
+# A fatal signal prints the raw backtrace, then names the frames
+# backtrace_symbols_fd() leaves as module+offset (-fvisibility=hidden hides them).
+set -eu
+
+testdir=$(cd "$(dirname "$0")" && pwd)
+# shellcheck source=tests/testlib.sh
+. "${testdir}/testlib.sh"
+
+if is_windows; then
+    echo "no backtrace() on Windows; skipping" >&2
+    exit 77
+fi
+command -v httrack >/dev/null || {
+    echo "could not find httrack" >&2
+    exit 1
+}
+
+tmpdir=$(mktemp -d "${TMPDIR:-/tmp}/httrack_symbolize.XXXXXX") || exit 1
+trap 'rm -rf "$tmpdir"' EXIT HUP INT QUIT PIPE TERM
+out="${tmpdir}/trace"
+raw="${tmpdir}/trace-optout"
+overflow="this string is far too long for the buffer"
+# A frame glibc could not name. Stop at the offset: it prints the trailing
+# "[0xADDR]" with or without a leading space depending on its version.
+rawframe='(+0x[0-9a-f][0-9a-f]*)'
+
+# The strsafe selftest aborts on purpose, which lands in sig_fatal.
+rc=0
+run_with_timeout 60 httrack -#test=strsafe overflow "$overflow" >"$out" 2>&1 || rc=$?
+test "$rc" -ne 124 || {
+    echo "the crash handler did not finish within the deadline" >&2
+    exit 1
+}
+
+grep -q '^Caught signal ' "$out" || {
+    echo "no 'Caught signal' line:" >&2
+    cat "$out" >&2
+    exit 1
+}
+if grep -q 'No stack trace available on this OS' "$out"; then
+    echo "no backtrace() on this platform; skipping" >&2
+    exit 77
+fi
+# Unconditional and first: symbolizing must never cost the raw trace.
+grep -q "$rawframe" "$out" || {
+    echo "raw module+offset frames are gone:" >&2
+    cat "$out" >&2
+    exit 1
+}
+
+command -v addr2line >/dev/null || {
+    echo "addr2line not installed; skipping" >&2
+    exit 77
+}
+
+# Control: resolve the same frames ourselves, so a stripped build cannot turn
+# the assertion below into a vacuous pass.
+oracle="${tmpdir}/oracle"
+sed -n 's/^\([^(]*\)(+\(0x[0-9a-f]*\)).*$/\1 \2/p' "$out" |
+    while read -r mod off; do
+        test -f "$mod" || continue
+        addr2line -Cfip -e "$mod" "$off" 2>/dev/null || true
+    done >"$oracle"
+grep -qE 'st_strsafe|strcpy_safe_' "$oracle" || {
+    echo "addr2line names no hidden symbol in this build; skipping" >&2
+    exit 77
+}
+
+# The payload. Dropping the raw frames first is what makes it specific: both
+# names are static, so .dynsym could never have carried them. Not anchored on
+# the "0xOFF:" line, the inline chain puts the name on either half.
+grep -v "$rawframe" "$out" | grep -qE 'st_strsafe|strcpy_safe_' || {
+    echo "the handler did not name the hidden frames:" >&2
+    cat "$out" >&2
+    exit 1
+}
+
+# Opt-out: raw trace kept, nothing spawned.
+export HTTRACK_NO_SYMBOLIZE=1
+rc=0
+run_with_timeout 60 httrack -#test=strsafe overflow "$overflow" >"$raw" 2>&1 || rc=$?
+unset HTTRACK_NO_SYMBOLIZE
+test "$rc" -ne 124 || {
+    echo "the opt-out run did not finish within the deadline" >&2
+    exit 1
+}
+grep -q "$rawframe" "$raw" || {
+    echo "the opt-out lost the raw trace:" >&2
+    cat "$raw" >&2
+    exit 1
+}
+! grep -q '^0x[0-9a-f]*: ' "$raw" || {
+    echo "the opt-out still symbolized:" >&2
+    cat "$raw" >&2
+    exit 1
+}

tests/81_webhttrack-maxsize.test

@@ -0,0 +1,142 @@
+#!/bin/bash
+#
+# The wizard's size fields must render as distinct caps: sizemax is -M, othermax
+# then maxhtml share -m.
+
+set -euo pipefail
+
+testdir=$(cd "$(dirname "$0")" && pwd)
+distdir=${top_srcdir:-$(cd "${testdir}/.." && pwd)}
+distdir=$(cd "${distdir}" && pwd)
+# shellcheck source=tests/testlib.sh
+. "${testdir}/testlib.sh"
+
+fail() {
+    echo "FAIL: $*" >&2
+    exit 1
+}
+
+command -v htsserver >/dev/null || fail "no htsserver in PATH"
+python=$(find_python) || {
+    echo "python3 not found; skipping" >&2
+    exit 77
+}
+
+work=$(mktemp -d "${TMPDIR:-/tmp}/webhttrack_maxsize.XXXXXX") || fail "no tmpdir"
+srvlog=$(mktemp)
+srv=
+cleanup() {
+    # htsserver keeps SIGTERM ignored across its exec, so only -9 reaps it.
+    test -z "${srv}" || kill -9 "${srv}" 2>/dev/null || true
+    wait "${srv}" 2>/dev/null || true # absorb bash's async "Killed" notice
+    srv=
+    rm -rf "${work}" "${srvlog}"
+}
+trap cleanup EXIT HUP INT QUIT PIPE TERM
+
+# webhttrack server on a pre-picked port; an isolated HOME keeps a stray
+# ~/.httrack.ini out of it.
+sport=$("${python}" -c 'import socket
+s = socket.socket()
+s.bind(("127.0.0.1", 0))
+print(s.getsockname()[1])
+s.close()')
+(
+    trap '' TERM TTOU
+    export HOME="${work}"
+    exec htsserver "${distdir}/" --port "${sport}" >"${srvlog}" 2>&1
+) &
+srv=$!
+for _ in $(seq 1 40); do
+    url=$(sed -n 's/^URL=//p' "${srvlog}") && test -n "${url}" && break
+    kill -0 "${srv}" 2>/dev/null || break
+    sleep 0.25
+done
+test -n "${url:-}" || fail "htsserver did not start: $(cat "${srvlog}")"
+
+# Audit what step4.html renders back; without command_do nothing is launched.
+"${python}" - "${url}" <<'PY' || fail "wizard rendered the wrong options (see above)"
+import re, sys, urllib.parse, urllib.request
+
+url = sys.argv[1]
+html, other, site = "111111", "222222", "333333"
+
+
+def post(fields):
+    # The body is refused without the session id the server puts in each form.
+    form = urllib.request.urlopen(url + "server/index.html", timeout=20).read()
+    m = re.search(rb'name="sid" value="([0-9a-f]+)"', form)
+    if not m:
+        raise SystemExit("no session id in server/index.html")
+    fields = [("sid", m.group(1).decode())] + fields
+    body = "&".join("%s=%s" % (k, urllib.parse.quote(v)) for k, v in fields)
+    req = urllib.request.Request(url + "server/step4.html",
+                                 data=body.encode("latin-1"), method="POST")
+    return urllib.request.urlopen(req, timeout=20).read().decode("latin-1")
+
+
+def textarea(page, name):
+    m = re.search(r'<textarea name="%s".*?>(.*?)</textarea>' % name, page, re.S)
+    if m is None:
+        sys.exit("no %s textarea in the rendered step4.html" % name)
+    return m.group(1)
+
+
+def want(ok, msg, ctx):
+    if not ok:
+        sys.exit("%s\nrendered:%s" % (msg, ctx))
+
+
+page = post([("maxhtml", html), ("othermax", other), ("sizemax", site),
+             ("dos", "2")])
+cmd = textarea(page, "command")
+want("--max-size=" + site in cmd, "site cap not emitted as --max-size", cmd)
+want("--max-files=" + site not in cmd, "site cap still an --max-files", cmd)
+# Positive controls: both per-file caps still ride -m, one option each.
+want("--max-files=" + other in cmd, "non-HTML cap not emitted as --max-files",
+     cmd)
+want("--max-files=," + html in cmd, "HTML cap not emitted as --max-files=,",
+     cmd)
+want(cmd.count("--max-files=") == 2, "unexpected --max-files count", cmd)
+want(cmd.index("--max-files=" + other) < cmd.index("--max-files=," + html),
+     "the bare --max-files must precede the --max-files=, form", cmd)
+
+# winprofile.ini feeds the same three caps to the Windows GUI, one key each.
+ini = textarea(page, "winprofile").replace("\r\n", "\n")  # the ini is CRLF
+want("\nDos=2" in ini, "Dos not written from the dos field", ini)
+want("\nMaxHtml=" + html + "\n" in ini, "MaxHtml not written from maxhtml", ini)
+want("\nMaxOther=" + other + "\n" in ini, "MaxOther not written from othermax",
+     ini)
+want("\nMaxAll=" + site + "\n" in ini, "MaxAll not written from sizemax", ini)
+
+# A bare --max-files= (an unguarded empty field) parses as -m with no digits,
+# silently clearing the html cap.
+page = post([("maxhtml", ""), ("othermax", ""), ("sizemax", ""), ("dos", "2")])
+cmd = textarea(page, "command")
+want("--max-rate=" in cmd, "empty size fields rendered no command line", cmd)
+want("--max-files" not in cmd and "--max-size" not in cmd,
+     "empty size fields still rendered a size option", cmd)
+
+# A mistyped ${LANG_OK] key renders the OK button's label empty.
+opts = urllib.request.urlopen(url + "server/option2b.html",
+                              timeout=20).read().decode("latin-1")
+want("LANG_OK" not in opts, "unexpanded LANG_OK in option2b.html", "")
+want('<input type="submit" value="OK"' in opts, "no OK label in option2b.html",
+     "")
+PY
+
+cleanup
+
+# A bare -m<n> resets the html limit, so only the bare-then-comma order keeps
+# both caps live. basic.html is 487 bytes, well past the 10-byte html cap.
+crawl() {
+    bash "${distdir}/tests/local-crawl.sh" "$@"
+}
+crawl --errors 1 --log-found 'File too big' \
+    httrack 'BASEURL/simple/basic.html' '--max-files=,10'
+crawl --errors 1 --log-found 'File too big' \
+    httrack 'BASEURL/simple/basic.html' '--max-files=500000' '--max-files=,10'
+crawl --errors 0 --found 'simple/basic.html' --log-not-found 'File too big' \
+    httrack 'BASEURL/simple/basic.html' '--max-files=,10' '--max-files=500000'
+
+echo "PASS"

tests/83_webhttrack-argescape.test

@@ -0,0 +1,148 @@
+#!/bin/bash
+#
+# The wizard renders its httrack command line as one string, which the engine
+# splits back into argv: a double quote in a field must reach the split escaped,
+# or the rest of the value is parsed as fresh options (-V runs a shell command).
+
+set -euo pipefail
+
+testdir=$(cd "$(dirname "$0")" && pwd)
+distdir=${top_srcdir:-$(cd "${testdir}/.." && pwd)}
+distdir=$(cd "${distdir}" && pwd)
+
+fail() {
+    echo "FAIL: $*" >&2
+    exit 1
+}
+
+command -v htsserver >/dev/null || fail "no htsserver in PATH"
+command -v python3 >/dev/null || {
+    echo "python3 not found; skipping" >&2
+    exit 77
+}
+
+srv=
+log=$(mktemp)
+cleanup() {
+    test -z "${srv}" || kill -9 "${srv}" 2>/dev/null || true
+    rm -f "${log}"
+}
+trap cleanup EXIT HUP INT QUIT PIPE TERM
+
+freeport() {
+    python3 -c 'import socket
+s = socket.socket()
+s.bind(("127.0.0.1", 0))
+print(s.getsockname()[1])
+s.close()'
+}
+
+# Echo the announced URL. Runs in a command substitution, so it is a
+# subshell and cannot export the pid: the caller reads it back with srvpid.
+start() {
+    local port url
+    port=$(freeport)
+    : >"${log}"
+    (
+        trap '' TERM TTOU
+        exec htsserver "${distdir}/" --port "${port}" >"${log}" 2>&1
+    ) &
+    for _ in $(seq 1 40); do
+        url=$(sed -n 's/^URL=//p' "${log}" 2>/dev/null) && test -n "${url}" && break
+        sleep 0.25
+    done
+    test -n "${url:-}" || fail "htsserver did not come up: $(cat "${log}")"
+    echo "${url}"
+}
+
+srvpid() { sed -n 's/^PID=//p' "${log}" | head -1; }
+
+portof() { echo "${1##*:}" | tr -d /; }
+
+# Raw request to 127.0.0.1:$1; $2 is the body ("" for a GET of the $3 page,
+# default index). Prints the reply.
+request() {
+    python3 -c 'import socket, sys
+port, body = int(sys.argv[1]), sys.argv[2]
+page = sys.argv[3] if len(sys.argv) > 3 else "index"
+if body:
+    req = ("POST / HTTP/1.0\r\nHost: 127.0.0.1\r\n"
+           "Content-type: application/x-www-form-urlencoded\r\n"
+           "Content-length: %d\r\n\r\n%s" % (len(body), body))
+else:
+    req = ("GET /server/%s.html HTTP/1.0\r\nHost: 127.0.0.1\r\n\r\n" % page)
+s = socket.create_connection(("127.0.0.1", port), 10)
+s.settimeout(30)
+s.sendall(req.encode())
+out = b""
+while True:
+    b = s.recv(65536)
+    if not b:
+        break
+    out += b
+s.close()
+sys.stdout.write(out.decode("latin-1"))' "$1" "$2" ${3+"$3"}
+}
+
+scrape_sid() {
+    request "$1" "" | sed -n 's/.*name="sid" value="\([0-9a-f]*\)".*/\1/p' | head -1
+}
+
+# urlencode the key=value pairs given as arguments
+formencode() {
+    python3 -c 'import sys, urllib.parse
+print(urllib.parse.urlencode([tuple(a.split("=", 1)) for a in sys.argv[1:]]))' "$@"
+}
+
+url=$(start)
+port=$(portof "${url}")
+srv=$(srvpid)
+test -n "${srv}" || fail "htsserver did not report its pid"
+
+sid=$(scrape_sid "${port}")
+test "${#sid}" -eq 32 || fail "did not scrape a 32-hex sid from the page (got '${sid}')"
+
+# Fill the wizard fields the command line quotes, then read back the generated
+# command line: the user-agent carries a break-out attempt, the footer a
+# backslash (which must survive the escape round trip), the project name a plain
+# value.
+body=$(formencode "sid=${sid}" 'user=Moz" -V "touch /tmp/pwn' 'footer=a\b"c' \
+    "path=/tmp/p" "projname=plain proj" 'urls=http://x/a"b' 'url2=+*.png"')
+request "${port}" "${body}" >/dev/null
+cmdline=$(request "${port}" "" step4 |
+    sed -n '/<textarea name="command"/,/<\/textarea>/p')
+
+# Control: without the fields in the page every assertion below is vacuous.
+grep -q -- '--user-agent' <<<"${cmdline}" ||
+    fail "no --user-agent in the generated command line (probe blind)"
+
+# A plain value is passed through untouched: the escaping must not mangle the
+# ordinary case.
+grep -qF -- '--path "/tmp/p/plain proj"' <<<"${cmdline}" ||
+    fail "a plain quoted value was not passed through: ${cmdline}"
+
+# The quote is escaped, so the split keeps it inside the value...
+grep -qF -- '--user-agent "Moz\" -V \"touch /tmp/pwn"' <<<"${cmdline}" ||
+    fail "the quote in the user-agent was not escaped: ${cmdline}"
+
+# ...and the raw form, which would end the argument and hand -V to the option
+# parser, is gone.
+grep -qF -- '--user-agent "Moz" -V "touch' <<<"${cmdline}" &&
+    fail "the user-agent still closes its argument early: ${cmdline}"
+
+# A backslash is escaped too, or the split would eat it along with the quote
+# that follows.
+grep -qF -- '--footer "a\\b\"c"' <<<"${cmdline}" ||
+    fail "the backslash in the footer was not escaped: ${cmdline}"
+
+# The url and filter fields sit outside quotes, where a backslash cannot escape
+# anything: one quote there flips the parity of every quote after it, so the
+# escaping above would protect nothing. They must not emit a raw quote at all.
+grep -qF -- 'http://x/a%22b' <<<"${cmdline}" ||
+    fail "the quote in the url field was not neutralised: ${cmdline}"
+grep -qF -- '+*.png%22' <<<"${cmdline}" ||
+    fail "the quote in the filter field was not neutralised: ${cmdline}"
+grep -qF -- 'http://x/a"b' <<<"${cmdline}" &&
+    fail "the url field still emits a raw quote: ${cmdline}"
+
+echo "PASS"

tests/Makefile.am

@@ -32,6 +32,7 @@ TESTS = \
 	00_runnable.test \
 	01_engine-charset.test \
 	01_engine-cmdline.test \
+	01_engine-cmdline-split.test \
 	01_engine-cookies.test \
 	01_engine-copyopt.test \
 	01_engine-crange.test \
@@ -174,6 +175,10 @@ TESTS = \
 	75_engine-longpath-posix.test \
 	76_cli-resize.test \
 	77_webhttrack-redirect.test \
-	78_webhttrack-sid.test
+	78_webhttrack-sid.test \
+	79_local-proxytrack-webdav-mime.test \
+	80_engine-crash-symbolize.test \
+	81_webhttrack-maxsize.test \
+	83_webhttrack-argescape.test
 
 CLEANFILES = check-network_sh.cache