htsparse: extract HT_ADD_END into hts_finish_html_file, drop dead macros

The final HTML-flush step lived in the ~60-line HT_ADD_END macro, captured by
lexical scope in htsparse(). Move it to a real function in htscore.c (next to
its sibling hts_finish_makeindex), passing the output buffer as a plain
pointer+length since the TypedArray is an anonymous struct type that can't cross
a function boundary; the caller keeps the size guard and the trailing
TypedArrayFree. Behavior-preserving: a two-crawl mirror produces byte-identical
output against master.

Also delete the _FILTERS/_FILTERS_PTR macros, dead in htsparse.c (htscore.c and
htswizard.c keep their own local copies); _ROBOTS stays.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Signed-off-by: Xavier Roche <roche@httrack.com>

debian/control

@@ -1,9 +1,8 @@
 Source: httrack
 Section: web
-Priority: optional
 Maintainer: Xavier Roche <roche@httrack.com>
 Standards-Version: 4.7.4
-Build-Depends: debhelper-compat (= 13), autoconf, autoconf-archive, automake, libtool, zlib1g-dev, libssl-dev
+Build-Depends: debhelper-compat (= 14), autoconf, autoconf-archive, automake, libtool, zlib1g-dev, libssl-dev
 Rules-Requires-Root: no
 Homepage: http://www.httrack.com
 Vcs-Git: https://github.com/xroche/httrack.git

debian/source/lintian-overrides

@@ -1,4 +1,6 @@
-httrack source: changelog-should-mention-nmu
+# Maintainer uploads sign the changelog as xavier@debian.org while the control
+# Maintainer is roche@httrack.com; lintian reads the address mismatch as an NMU.
+httrack source: no-nmu-in-changelog
 httrack source: source-nmu-has-incorrect-version-number
 
 # The bundled HTML pages are the genuine upstream documentation taken from

debian/upstream/metadata

@@ -0,0 +1,6 @@
+---
+Repository: https://github.com/xroche/httrack.git
+Repository-Browse: https://github.com/xroche/httrack
+Bug-Database: https://github.com/xroche/httrack/issues
+Bug-Submit: https://github.com/xroche/httrack/issues/new
+Contact: Xavier Roche <roche@httrack.com>

src/htscore.c

@@ -406,29 +406,106 @@ void hts_invalidate_link(httrackp * opt, int lpos) {
   opt->liens[lpos]->pass2 = -1;
 }
 
+// Write the makeindex footer (refresh meta when makeindex_links==1), close
+// the file, then run usercommand.
+void hts_finish_makeindex(httrackp *opt, int *makeindex_done,
+                          FILE **makeindex_fp, int makeindex_links,
+                          const char *makeindex_firstlink,
+                          const char *template_footer, const char *adr,
+                          const char *fil) {
+  if (!*makeindex_done) {
+    if (*makeindex_fp) {
+      char BIGSTK tempo[1024];
+      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);
+      } else
+        tempo[0] = '\0';
+      hts_template_format(*makeindex_fp, template_footer,
+                          "<!-- Mirror and index made by HTTrack Website "
+                          "Copier/" HTTRACK_VERSION " " HTTRACK_AFF_AUTHORS
+                          " -->",
+                          tempo, /* EOF */ NULL);
+      fflush(*makeindex_fp);
+      fclose(*makeindex_fp);
+      *makeindex_fp = NULL;
+      usercommand(opt, 0, NULL,
+                  fconcat(OPT_GET_BUFF(opt), OPT_GET_BUFF_SIZE(opt),
+                          StringBuff(opt->path_html_utf8), "index.html"),
+                  adr, fil);
+    }
+  }
+  *makeindex_done = 1;
+}
 
-#define HT_INDEX_END do { \
-if (!makeindex_done) { \
-if (makeindex_fp) { \
-  char BIGSTK tempo[1024]; \
-  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); \
-  } else \
-    tempo[0]='\0'; \
-    hts_template_format(makeindex_fp,template_footer, \
-    "<!-- Mirror and index made by HTTrack Website Copier/"HTTRACK_VERSION" "HTTRACK_AFF_AUTHORS" -->", \
-    tempo, /* EOF */ NULL \
-    ); \
-  fflush(makeindex_fp); \
-  fclose(makeindex_fp);  /* à ne pas oublier sinon on passe une nuit blanche */  \
-  makeindex_fp=NULL; \
-  usercommand(opt,0,NULL,fconcat(OPT_GET_BUFF(opt),OPT_GET_BUFF_SIZE(opt),StringBuff(opt->path_html_utf8),"index.html"),"","");  \
-} \
-} \
-makeindex_done=1;    /* ok c'est fait */  \
-} while(0)
+/* Flush the parsed HTML output buffer to disk, skipping the rewrite when the
+ * on-disk MD5 is unchanged. */
+void hts_finish_html_file(httrackp *opt, cache_back *cache, htsblk *r,
+                          FILE **fp, const char *ht_buff, size_t ht_len,
+                          const char *adr, const char *fil, const char *save) {
+  char digest[32 + 2];
+  off_t fsize_old =
+      fsize(fconv(OPT_GET_BUFF(opt), OPT_GET_BUFF_SIZE(opt), save));
+  int ok = 0;
+
+  digest[0] = '\0';
+  domd5mem(ht_buff, ht_len, digest, 1);
+  if (fsize_old == (off_t) ht_len) {
+    int mlen = 0;
+    char *mbuff;
+
+    cache_readdata(cache, "//[HTML-MD5]//", save, &mbuff, &mlen);
+    if (mlen)
+      mbuff[mlen] = '\0';
+    if ((mlen == 32) && (strcmp(((mbuff != NULL) ? mbuff : ""), digest) == 0)) {
+      ok = 1;
+      hts_log_print(opt, LOG_DEBUG, "File not re-written (md5): %s", save);
+    }
+    freet(mbuff);
+  }
+  if (!ok) {
+    file_notify(opt, adr, fil, save, 1, 1, r->notmodified);
+    *fp = filecreate(&opt->state.strc, save);
+    if (*fp) {
+      if (ht_len > 0 && fwrite(ht_buff, 1, ht_len, *fp) != ht_len) {
+        int fcheck = check_fatal_io_errno();
+
+        if (fcheck)
+          opt->state.exit_xh = -1;
+        if (opt->log) {
+          hts_log_print(opt, LOG_ERROR | LOG_ERRNO,
+                        "Unable to write HTML file %s", save);
+          if (fcheck)
+            hts_log_print(opt, LOG_ERROR, "* * Fatal write error, giving up");
+        }
+      }
+      fclose(*fp);
+      *fp = NULL;
+      if (strnotempty(r->lastmodified))
+        set_filetime_rfc822(save, r->lastmodified);
+    } else {
+      int fcheck = check_fatal_io_errno();
+
+      if (fcheck) {
+        hts_log_print(opt, LOG_ERROR,
+                      "Mirror aborted: disk full or filesystem problems");
+        opt->state.exit_xh = -1;
+      }
+      hts_log_print(opt, LOG_ERROR | LOG_ERRNO, "Unable to save file %s", save);
+      if (fcheck)
+        hts_log_print(opt, LOG_ERROR, "* * Fatal write error, giving up");
+    }
+  } else {
+    file_notify(opt, adr, fil, save, 0, 0, r->notmodified);
+    filenote(&opt->state.strc, save, NULL);
+  }
+  if (cache->ndx)
+    cache_writedata(cache->ndx, cache->dat, "//[HTML-MD5]//", save, digest,
+                    (int) strlen(digest));
+}
 
 /* does it look like XML ? (SVG et al.) */
 static int look_like_xml(const char *s) {
@@ -2044,7 +2121,8 @@ int httpmirror(char *url1, httrackp * opt) {
   /*
      Ensure the index is being closed
    */
-  HT_INDEX_END;
+  hts_finish_makeindex(opt, &makeindex_done, &makeindex_fp, makeindex_links,
+                       makeindex_firstlink, template_footer, "", "");
 
   /* 
      updating-a-remotely-deteted-website hack

src/htscore.h

@@ -362,6 +362,20 @@ void usercommand(httrackp * opt, int exe, const char *cmd, const char *file,
 
 void usercommand_exe(const char *cmd, const char *file);
 
+// Finish the makeindex index.html (footer + refresh meta), run usercommand.
+// Updates *makeindex_done/*makeindex_fp in place; adr/fil are the mode strings.
+void hts_finish_makeindex(httrackp *opt, int *makeindex_done,
+                          FILE **makeindex_fp, int makeindex_links,
+                          const char *makeindex_firstlink,
+                          const char *template_footer, const char *adr,
+                          const char *fil);
+
+// Flush ht_buff[0..ht_len] to save on disk (skip if MD5 unchanged); *fp
+// closed+NULLed on write. Precondition: ht_len>0.
+void hts_finish_html_file(httrackp *opt, cache_back *cache, htsblk *r,
+                          FILE **fp, const char *ht_buff, size_t ht_len,
+                          const char *adr, const char *fil, const char *save);
+
 int filters_init(char ***ptrfilters, int maxfilter, int filterinc);
 
 int fspc(httrackp * opt, FILE * fp, const char *type);
@@ -470,4 +484,8 @@ void voidf(void);
 /* HTML marker comment marking where the top index is spliced. */
 #define HTS_TOPINDEX "TOP_INDEX_HTTRACK"
 
+/* Worst-case byte expansion HT_ADD_HTMLESCAPED* must reserve per escaper. */
+#define HTS_HTMLESCAPE_MAXEXP 5      /* escape_for_html_print: '&'->"&" */
+#define HTS_HTMLESCAPE_FULL_MAXEXP 6 /* _full: high byte->"&#xHH;" */
+
 #endif

src/htslib.c

@@ -4131,25 +4131,33 @@ DECLARE_APPEND_ESCAPE_VERSION(escape_uri)
 
 #undef DECLARE_APPEND_ESCAPE_VERSION
 
-// Same as above, but in-place
-#undef DECLARE_INPLACE_ESCAPE_VERSION
-#define DECLARE_INPLACE_ESCAPE_VERSION(NAME) \
-HTSEXT_API size_t inplace_ ##NAME(char *const dest, const size_t size) { \
-  char buffer[256]; \
-  const size_t len = strnlen(dest, size); \
-  const int in_buffer = len + 1 < sizeof(buffer); \
-  char *src = in_buffer ? buffer : malloct(len + 1); \
-  size_t ret; \
-  assertf(src != NULL); \
-  assertf(len < size); \
-  memcpy(src, dest, len + 1); \
-  ret = NAME(src, dest, size); \
-  if (!in_buffer) { \
-    freet(src); \
-  } \
-  return ret; \
+// In-place escaping: copy dest aside, then escape that copy back into dest.
+typedef size_t (*escape_fn_t)(const char *src, char *dest, size_t size);
+
+static size_t inplace_escape(char *const dest, const size_t size,
+                             escape_fn_t escape) {
+  char buffer[256];
+  const size_t len = strnlen(dest, size);
+  const int in_buffer = len + 1 < sizeof(buffer);
+  char *src = in_buffer ? buffer : malloct(len + 1);
+  size_t ret;
+  assertf(src != NULL);
+  assertf(len < size);
+  memcpy(src, dest, len + 1);
+  ret = escape(src, dest, size);
+  if (!in_buffer) {
+    freet(src);
+  }
+  return ret;
 }
 
+// Thin exported wrappers binding inplace_escape() to each escaper (ABI).
+#undef DECLARE_INPLACE_ESCAPE_VERSION
+#define DECLARE_INPLACE_ESCAPE_VERSION(NAME)                                   \
+  HTSEXT_API size_t inplace_##NAME(char *const dest, const size_t size) {      \
+    return inplace_escape(dest, size, NAME);                                   \
+  }
+
 DECLARE_INPLACE_ESCAPE_VERSION(escape_in_url)
 DECLARE_INPLACE_ESCAPE_VERSION(escape_spc_url)
 DECLARE_INPLACE_ESCAPE_VERSION(escape_uri_utf)

src/htsparse.c

@@ -77,13 +77,14 @@ Please visit our Website: http://www.httrack.com
 /** Append to the output buffer the string 'A'. **/
 #define HT_ADD(A) TypedArrayAppend(output_buffer, A, strlen(A))
 
-/** Append to the output buffer the string 'A', html-escaped. **/
-#define HT_ADD_HTMLESCAPED_ANY(A, FUNCTION) do { \
+/* clang-format off: an edit realigns all backslashes, churning the macro. */
+/* clang-format off */
+/** Append 'A' to the output buffer, html-escaped; FACTOR = max byte expansion. **/
+#define HT_ADD_HTMLESCAPED_ANY(A, FUNCTION, FACTOR) do { \
   if ((opt->getmode & 1) != 0 && ptr>0) { \
     const char *const str_ = (A); \
     size_t size_; \
-    /* & is the maximum expansion */ \
-    TypedArrayEnsureRoom(output_buffer, strlen(str_) * 5 + 1024); \
+    TypedArrayEnsureRoom(output_buffer, strlen(str_) * (FACTOR) + 1024); \
     size_ = FUNCTION(str_, &TypedArrayTail(output_buffer), \
                      TypedArrayRoom(output_buffer)); \
     TypedArraySize(output_buffer) += size_; \
@@ -91,106 +92,22 @@ Please visit our Website: http://www.httrack.com
 } while(0)
 
 /** Append to the output buffer the string 'A', html-escaped for &. **/
-#define HT_ADD_HTMLESCAPED(A) HT_ADD_HTMLESCAPED_ANY(A, escape_for_html_print)
+#define HT_ADD_HTMLESCAPED(A) \
+  HT_ADD_HTMLESCAPED_ANY(A, escape_for_html_print, HTS_HTMLESCAPE_MAXEXP)
 
 /**
- * Append to the output buffer the string 'A', html-escaped for & and 
+ * Append to the output buffer the string 'A', html-escaped for & and
  * high chars.
  **/
-#define HT_ADD_HTMLESCAPED_FULL(A) HT_ADD_HTMLESCAPED_ANY(A, escape_for_html_print_full)
+#define HT_ADD_HTMLESCAPED_FULL(A) \
+  HT_ADD_HTMLESCAPED_ANY(A, escape_for_html_print_full, HTS_HTMLESCAPE_FULL_MAXEXP)
+/* clang-format on */
 
 // does nothing
 #define XH_uninit do {} while(0)
 
-#define HT_ADD_END { \
-  int ok=0;\
-  if (TypedArraySize(output_buffer) != 0) { \
-    const size_t ht_len = TypedArraySize(output_buffer); \
-    const char *const ht_buff = TypedArrayElts(output_buffer); \
-    char digest[32+2];\
-    off_t fsize_old = fsize(fconv(OPT_GET_BUFF(opt),OPT_GET_BUFF_SIZE(opt),savename()));\
-    digest[0] = '\0';\
-    domd5mem(TypedArrayElts(output_buffer), ht_len, digest, 1);\
-    if (fsize_old == (off_t) ht_len) { \
-      int mlen = 0;\
-      char* mbuff;\
-      cache_readdata(cache,"//[HTML-MD5]//",savename(),&mbuff,&mlen);\
-      if (mlen) \
-        mbuff[mlen]='\0';\
-      if ((mlen == 32) && (strcmp(((mbuff!=NULL)?mbuff:""),digest)==0)) {\
-        ok=1;\
-        hts_log_print(opt, LOG_DEBUG, "File not re-written (md5): %s",savename());\
-      } else {\
-        ok=0;\
-      } \
-    }\
-    if (!ok) { \
-      file_notify(opt,urladr(), urlfil(), savename(), 1, 1, r->notmodified); \
-      fp=filecreate(&opt->state.strc, savename()); \
-      if (fp) { \
-        if (ht_len>0) {\
-        if (fwrite(ht_buff,1,ht_len,fp) != ht_len) { \
-          int fcheck;\
-          if ((fcheck=check_fatal_io_errno())) {\
-            opt->state.exit_xh=-1;\
-          }\
-          if (opt->log) {   \
-            hts_log_print(opt, LOG_ERROR | LOG_ERRNO, "Unable to write HTML file %s", savename());\
-            if (fcheck) {\
-              hts_log_print(opt, LOG_ERROR, "* * Fatal write error, giving up");\
-            }\
-          }\
-        }\
-        }\
-        fclose(fp); fp=NULL; \
-        if (strnotempty(r->lastmodified)) \
-        set_filetime_rfc822(savename(),r->lastmodified); \
-      } else {\
-        int fcheck;\
-        if ((fcheck=check_fatal_io_errno())) {\
-  				hts_log_print(opt, LOG_ERROR, "Mirror aborted: disk full or filesystem problems"); \
-          opt->state.exit_xh=-1;\
-        }\
-        hts_log_print(opt, LOG_ERROR | LOG_ERRNO, "Unable to save file %s", savename());\
-        if (fcheck) {\
-          hts_log_print(opt, LOG_ERROR, "* * Fatal write error, giving up");\
-        }\
-      }\
-    } else {\
-      file_notify(opt,urladr(), urlfil(), savename(), 0, 0, r->notmodified); \
-      filenote(&opt->state.strc, savename(),NULL); \
-    }\
-    if (cache->ndx)\
-      cache_writedata(cache->ndx,cache->dat,"//[HTML-MD5]//",savename(),digest,(int)strlen(digest));\
-  } \
-  TypedArrayFree(output_buffer); \
-}
 #define HT_ADD_FOP
 
-// COPY IN HTSCORE.C
-#define HT_INDEX_END do { \
-  if (!makeindex_done) { \
-  if (makeindex_fp) { \
-  char BIGSTK tempo[1024]; \
-  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); \
-  } else \
-  tempo[0]='\0'; \
-  hts_template_format(makeindex_fp,template_footer, \
-  "<!-- Mirror and index made by HTTrack Website Copier/"HTTRACK_VERSION" "HTTRACK_AFF_AUTHORS" -->", \
-  tempo, /* EOF */ NULL \
-  ); \
-  fflush(makeindex_fp); \
-  fclose(makeindex_fp);  /* à ne pas oublier sinon on passe une nuit blanche */  \
-  makeindex_fp=NULL; \
-  usercommand(opt,0,NULL,fconcat(OPT_GET_BUFF(opt), OPT_GET_BUFF_SIZE(opt),  StringBuff(opt->path_html_utf8),"index.html"),"primary","primary");  \
-  } \
-  } \
-  makeindex_done=1;    /* ok c'est fait */  \
-} while(0)
-
 #define ENGINE_DEFINE_CONTEXT() \
   ENGINE_DEFINE_CONTEXT_BASE(); \
   /* */ \
@@ -217,6 +134,9 @@ Please visit our Website: http://www.httrack.com
   HTS_UNUSED TStamp makestat_time = stre->makestat_time; \
   HTS_UNUSED FILE* makestat_fp = stre->makestat_fp
 
+/* clang-format off: an edit realigns all backslashes, churning the macro. */
+/* clang-format off */
+/* Load-once: re-reading resets makestat_time (mutated locally, never SAVEd). */
 #define ENGINE_SET_CONTEXT() \
   ENGINE_SET_CONTEXT_BASE(); \
   /* */ \
@@ -227,9 +147,8 @@ Please visit our Website: http://www.httrack.com
   makeindex_fp = *stre->makeindex_fp_; \
   makeindex_links = *stre->makeindex_links_; \
   /* */ \
-  stat_fragment = *stre->stat_fragment_; \
-  makestat_time = stre->makestat_time; \
-  makestat_fp = stre->makestat_fp
+  stat_fragment = *stre->stat_fragment_
+/* clang-format on */
 
 #define ENGINE_LOAD_CONTEXT() \
   ENGINE_DEFINE_CONTEXT()
@@ -246,8 +165,6 @@ Please visit our Website: http://www.httrack.com
   /* */ \
   *stre->stat_fragment_ = stat_fragment
 
-#define _FILTERS     (*opt->filters.filters)
-#define _FILTERS_PTR (opt->filters.filptr)
 #define _ROBOTS      ((robots_wizard*)opt->robotsptr)
 
 /* Apply current *adr character for the script automate */
@@ -709,7 +626,9 @@ int htsparse(htsmoduleStruct * str, htsmoduleStructExtended * stre) {
               }
 
             } else if (heap(ptr)->depth < opt->depth) {        // on a sauté level1+1 et level1
-              HT_INDEX_END;
+              hts_finish_makeindex(opt, &makeindex_done, &makeindex_fp,
+                                   makeindex_links, makeindex_firstlink,
+                                   template_footer, "primary", "primary");
             }
           }                     // if (opt->makeindex)
         }
@@ -3540,7 +3459,12 @@ int htsparse(htsmoduleStruct * str, htsmoduleStructExtended * stre) {
         }
 
         /* Flush and save to disk */
-        HT_ADD_END;             // achever
+        if (TypedArraySize(output_buffer) != 0) {
+          hts_finish_html_file(
+              opt, cache, r, &fp, TypedArrayElts(output_buffer),
+              TypedArraySize(output_buffer), urladr(), urlfil(), savename());
+        }
+        TypedArrayFree(output_buffer);
       }
       //
       //

src/htsselftest.c

@@ -524,6 +524,41 @@ static int string_safety_selftests(void) {
       return 1;
   }
 
+  /* StringCatN/StringSetLength must eval SIZE once: (n_eval++, V) leaves
+     n_eval == 2 on a double-eval macro. */
+  {
+    String s = STRING_EMPTY;
+    int n_eval = 0;
+
+    StringCat(s, "hello");
+    StringCatN(s, "world", (n_eval++, 3)); /* strlen>SIZE so the clamp runs */
+    if (n_eval != 1 || strcmp(StringBuff(s), "hellowor") != 0) {
+      StringFree(s);
+      return 1;
+    }
+
+    n_eval = 0;
+    StringSetLength(s, (n_eval++, 5));
+    if (n_eval != 1 || StringLength(s) != 5) {
+      StringFree(s);
+      return 1;
+    }
+    StringFree(s);
+  }
+
+  /* StringSubRW still reads/writes after dropping its duplicate definition. */
+  {
+    String s = STRING_EMPTY;
+
+    StringCat(s, "abc");
+    StringSubRW(s, 1) = 'X';
+    if (StringSub(s, 1) != 'X' || strcmp(StringBuff(s), "aXc") != 0) {
+      StringFree(s);
+      return 1;
+    }
+    StringFree(s);
+  }
+
   return 0;
 }
 
@@ -1305,6 +1340,134 @@ static int st_urlhack(httrackp *opt, int argc, char **argv) {
   return 0;
 }
 
+// hts_finish_makeindex writes the footer, emits the refresh meta only when
+// makeindex_links==1, and clears *fp / sets *done. argv[0] is a writable dir.
+static int st_makeindex(httrackp *opt, int argc, char **argv) {
+  char path[HTS_URLMAXSIZE];
+  char buf[4096];
+  FILE *fp;
+  size_t n;
+  int done;
+
+  assertf(argc >= 1);
+  snprintf(path, sizeof(path), "%s/index.html", argv[0]);
+
+  /* single first link: footer + a refresh meta carrying the escaped URL */
+  done = 0;
+  fp = fopen(path, "wb");
+  assertf(fp != NULL);
+  hts_finish_makeindex(opt, &done, &fp, 1, "http://example.com/a b", "%s%s", "",
+                       "");
+  assertf(fp == NULL); /* the function closed and cleared it */
+  assertf(done != 0);
+  fp = fopen(path, "rb");
+  assertf(fp != NULL);
+  n = fread(buf, 1, sizeof(buf) - 1, fp);
+  fclose(fp);
+  buf[n] = '\0';
+  assertf(strstr(buf, "Mirror and index made by HTTrack") != NULL);
+  assertf(strstr(buf, "Refresh") != NULL);
+  assertf(strstr(buf, "example.com") != NULL);
+
+  /* no single link: footer only, no refresh meta */
+  done = 0;
+  fp = fopen(path, "wb");
+  assertf(fp != NULL);
+  hts_finish_makeindex(opt, &done, &fp, 0, NULL, "%s%s", "", "");
+  assertf(fp == NULL);
+  assertf(done != 0);
+  fp = fopen(path, "rb");
+  assertf(fp != NULL);
+  n = fread(buf, 1, sizeof(buf) - 1, fp);
+  fclose(fp);
+  buf[n] = '\0';
+  assertf(strstr(buf, "Mirror and index made by HTTrack") != NULL);
+  assertf(strstr(buf, "Refresh") == NULL);
+
+  UNLINK(path);
+  printf("makeindex self-test OK\n");
+  return 0;
+}
+
+/* Each inplace_escape_*() must equal escape_*() on a copy. */
+static int st_inplace_escape(httrackp *opt, int argc, char **argv) {
+  /* >255 bytes forces the helper's malloct path, not the stack buffer */
+  static char longstr[600];
+  static const char *const samples[] = {
+      "",          "abc",           "a b/c?d=e&f", "h\x8ello w\x94rld",
+      "a%b\"c<d>", "/path to/file", longstr};
+  static size_t (*const inplace[])(char *, size_t) = {
+      inplace_escape_in_url, inplace_escape_spc_url, inplace_escape_uri_utf,
+      inplace_escape_check_url, inplace_escape_uri};
+  static size_t (*const plain[])(const char *, char *, size_t) = {
+      escape_in_url, escape_spc_url, escape_uri_utf, escape_check_url,
+      escape_uri};
+  size_t i, f;
+
+  (void) opt;
+  (void) argc;
+  (void) argv;
+
+  memset(longstr, 'a', sizeof(longstr) - 1);
+  for (f = 0; f < sizeof(inplace) / sizeof(inplace[0]); f++) {
+    for (i = 0; i < sizeof(samples) / sizeof(samples[0]); i++) {
+      char ref[4096], work[4096];
+      size_t rret, iret;
+      rret = plain[f](samples[i], ref, sizeof(ref));
+      strcpybuff(work, samples[i]);
+      iret = inplace[f](work, sizeof(work));
+      assertf(iret == rret);
+      assertf(strcmp(work, ref) == 0);
+    }
+  }
+  printf("inplace-escape self-test OK\n");
+  return 0;
+}
+
+/* Pin HTS_HTMLESCAPE*_MAXEXP to each escaper's true max byte expansion. */
+static int st_escape_room(httrackp *opt, int argc, char **argv) {
+  /* N > 1023: where 6n outgrows the old 5n+1024 reservation */
+  enum { N = 2000 };
+
+  char *src = malloct(N + 1);
+  char *dst;
+  size_t room, got;
+  (void) opt;
+  (void) argc;
+  (void) argv;
+
+  /* _full worst case: a high byte expands to "&#xHH;" (6 bytes) */
+  memset(src, 0xE9, N);
+  src[N] = '\0';
+  room = (size_t) N * HTS_HTMLESCAPE_FULL_MAXEXP + 1024;
+  dst = malloct(room);
+  got = escape_for_html_print_full(src, dst, room);
+  assertf(got == (size_t) N * HTS_HTMLESCAPE_FULL_MAXEXP);
+  assertf(strlen(dst) == got);
+  freet(dst);
+
+  /* one factor short overflows (returns size), truncating the page: the bug */
+  room = (size_t) N * (HTS_HTMLESCAPE_FULL_MAXEXP - 1) + 1024;
+  dst = malloct(room);
+  got = escape_for_html_print_full(src, dst, room);
+  assertf(got == room);
+  freet(dst);
+
+  /* plain escaper worst case: '&' -> "&amp;" (5); high bytes stay verbatim */
+  memset(src, '&', N);
+  src[N] = '\0';
+  room = (size_t) N * HTS_HTMLESCAPE_MAXEXP + 1024;
+  dst = malloct(room);
+  got = escape_for_html_print(src, dst, room);
+  assertf(got == (size_t) N * HTS_HTMLESCAPE_MAXEXP);
+  assertf(strlen(dst) == got);
+  freet(dst);
+
+  freet(src);
+  printf("escape-room self-test OK\n");
+  return 0;
+}
+
 /* Default User-Agent: honest HTTrack token, no resurrected Windows 98. */
 static int st_useragent(httrackp *opt, int argc, char **argv) {
   const char *ua = StringBuff(opt->user_agent);
@@ -1621,6 +1784,12 @@ static const struct selftest_entry {
     {"dns", "", "DNS resolver/cache self-test", st_dns},
     {"cookies", "", "cookie request-header self-test", st_cookies},
     {"useragent", "", "default User-Agent self-test", st_useragent},
+    {"makeindex", "[dir]", "hts_finish_makeindex footer/refresh self-test",
+     st_makeindex},
+    {"inplace-escape", "", "inplace_escape_* vs escape_* equivalence self-test",
+     st_inplace_escape},
+    {"escape-room", "", "HT_ADD_HTMLESCAPED* reservation-factor self-test",
+     st_escape_room},
     {"status", "", "HTTP status code -> reason phrase self-test", st_status},
     {"acceptencoding", "[dir]",
      "Accept-Encoding advertises gzip+deflate, both decode", st_acceptencoding},

src/htsstrings.h

@@ -121,9 +121,6 @@ struct String {
 /** Byte at POS (read/write). No bounds check; POS must be < StringLength. **/
 #define StringSubRW(BLK, POS) (StringBuffRW(BLK)[POS])
 
-/** Subcharacter (read/write) **/
-#define StringSubRW(BLK, POS) (StringBuffRW(BLK)[POS])
-
 /** Byte POS positions from the end (read). POS==1 is the last byte. **/
 #define StringRight(BLK, POS) (StringBuff(BLK)[StringLength(BLK) - POS])
 
@@ -191,8 +188,9 @@ HTS_STATIC char *StringBuffN_(String *blk, int size) {
     asserts SIZE fits the existing content; does not (re)allocate. **/
 #define StringSetLength(BLK, SIZE)                                             \
   do {                                                                         \
-    if (SIZE >= 0) {                                                           \
-      (BLK).length_ = SIZE;                                                    \
+    const int len__ = (SIZE); /* signed: negative means strlen(buffer_) */     \
+    if (len__ >= 0) {                                                          \
+      (BLK).length_ = len__;                                                   \
     } else {                                                                   \
       (BLK).length_ = strlen((BLK).buffer_);                                   \
     }                                                                          \
@@ -308,10 +306,11 @@ HTS_STATIC void StringAttach(String *blk, char **str) {
 #define StringCatN(BLK, STR, SIZE)                                             \
   do {                                                                         \
     const char *str__ = (STR);                                                 \
+    const size_t usize__ = (SIZE);                                             \
     if (str__ != NULL) {                                                       \
       size_t size__ = strlen(str__);                                           \
-      if (size__ > (SIZE)) {                                                   \
-        size__ = (SIZE);                                                       \
+      if (size__ > usize__) {                                                  \
+        size__ = usize__;                                                      \
       }                                                                        \
       StringMemcat(BLK, str__, size__);                                        \
     }                                                                          \

tests/01_engine-escape-room.test

@@ -0,0 +1,7 @@
+#!/bin/bash
+#
+
+set -euo pipefail
+
+# HT_ADD_HTMLESCAPED* must reserve the escaper's worst case (6 for _full).
+httrack -O /dev/null -#test=escape-room run | grep -q "escape-room self-test OK"

tests/01_engine-inplace-escape.test

@@ -0,0 +1,7 @@
+#!/bin/bash
+#
+
+set -euo pipefail
+
+# inplace_escape_*() must match escape_*() on a copy: guards the shared helper.
+httrack -O /dev/null -#test=inplace-escape run | grep -q "inplace-escape self-test OK"

tests/01_engine-makeindex.test

@@ -0,0 +1,12 @@
+#!/bin/bash
+#
+
+set -euo pipefail
+
+# hts_finish_makeindex writes the footer and gates the refresh meta on a single
+# first link (guards the macro->function extraction).
+dir=$(mktemp -d)
+trap 'rm -rf "$dir"' EXIT
+
+httrack -O /dev/null -#test=makeindex "$dir" run |
+    grep -q "makeindex self-test OK"

tests/Makefile.am

@@ -36,6 +36,9 @@ TESTS = \
 	01_engine-filter.test \
 	01_engine-hashtable.test \
 	01_engine-idna.test \
+	01_engine-escape-room.test \
+	01_engine-inplace-escape.test \
+	01_engine-makeindex.test \
 	01_engine-mime.test \
 	01_engine-parse.test \
 	01_engine-pause.test \