Ability to specify multiple arguments to \cfg{html-template-fragment};

Halibut will output fragment names in all specified formats. (I forget now
precisely why I thought this was necessary, but it seems potentially useful.)

Also ensure that legal fragment names are generated even if none of the
characters from the original turn out to be legal (e.g., %k with an entirely
numeric keyword), and correct an untruth I inserted in the documentation of
this.

(This commit hits more than just the HTML backend as I've generalised an error
message, and fixed a fault in the info backend's error handling while there.)

[originally from svn r5457]

1 files changed, 97 insertions, 38 deletions

diff --git a/bk_html.c b/bk_html.c
index c98d932..4da897f 100644
--- a/bk_html.c
+++ b/bk_html.c
@@ -45,7 +45,8 @@ typedef struct {
     char *index_filename;
     char *template_filename;
     char *single_filename;
-    char *template_fragment;
+    char **template_fragments;
+    int ntfragments;
     char *head_end, *body_start, *body_end, *addr_start, *addr_end;
     char *body_tag, *nav_attr;
     wchar_t *author, *description;
@@ -84,7 +85,7 @@ struct htmlsect {
     paragraph *title, *text;
     enum { NORMAL, TOP, INDEX } type;
     int contents_depth;
-    char *fragment;
+    char **fragments;
 };
 
 typedef struct {
@@ -150,7 +151,8 @@ static void html_file_section(htmlconfig *cfg, htmlfilelist *files,
 			      htmlsect *sect, int depth);
 
 static htmlfile *html_new_file(htmlfilelist *list, char *filename);
-static htmlsect *html_new_sect(htmlsectlist *list, paragraph *title);
+static htmlsect *html_new_sect(htmlsectlist *list, paragraph *title,
+			       htmlconfig *cfg);
 
 /* Flags for html_words() flags parameter */
 #define NOTHING 0x00
@@ -217,7 +219,9 @@ static htmlconfig html_configure(paragraph *source) {
     ret.contents_filename = dupstr("Contents.html");
     ret.index_filename = dupstr("IndexPage.html");
     ret.template_filename = dupstr("%n.html");
-    ret.template_fragment = dupstr("%b");
+    ret.ntfragments = 1;
+    ret.template_fragments = snewn(ret.ntfragments, char *);
+    ret.template_fragments[0] = dupstr("%b");
     ret.head_end = ret.body_tag = ret.body_start = ret.body_end =
 	ret.addr_start = ret.addr_end = ret.nav_attr = NULL;
     ret.author = ret.description = NULL;
@@ -305,8 +309,24 @@ static htmlconfig html_configure(paragraph *source) {
 		sfree(ret.template_filename);
 		ret.template_filename = dupstr(adv(p->origkeyword));
 	    } else if (!ustricmp(k, L"html-template-fragment")) {
-		sfree(ret.template_fragment);
-		ret.template_fragment = dupstr(adv(p->origkeyword));
+		char *frag = adv(p->origkeyword);
+		if (*frag) {
+		    while (ret.ntfragments--)
+			sfree(ret.template_fragments[ret.ntfragments]);
+		    sfree(ret.template_fragments);
+		    ret.template_fragments = NULL;
+		    ret.ntfragments = 0;
+		    while (*frag) {
+			ret.ntfragments++;
+			ret.template_fragments =
+			    sresize(ret.template_fragments,
+				    ret.ntfragments, char *);
+			ret.template_fragments[ret.ntfragments-1] =
+			    dupstr(frag);
+			frag = adv(frag);
+		    }
+		} else
+		    error(err_cfginsufarg, &p->fpos, p->origkeyword, 1);
 	    } else if (!ustricmp(k, L"html-chapter-numeric")) {
 		ret.achapter.just_numbers = utob(uadv(k));
 	    } else if (!ustricmp(k, L"html-chapter-suffix")) {
@@ -490,20 +510,19 @@ void html_backend(paragraph *sourceform, keywordlist *keywords,
      * source form but needs to be consistently mentioned in
      * contents links.
      * 
-     * While we're here, we'll also invent the HTML fragment name
+     * While we're here, we'll also invent the HTML fragment name(s)
      * for each section.
      */
     {
 	htmlsect *topsect, *sect;
 	int d;
 
-	topsect = html_new_sect(&sects, NULL);
+	topsect = html_new_sect(&sects, NULL, &conf);
 	topsect->type = TOP;
 	topsect->title = NULL;
 	topsect->text = sourceform;
 	topsect->contents_depth = contents_depth(conf, 0);
 	html_file_section(&conf, &files, topsect, -1);
-	topsect->fragment = NULL;
 
 	for (p = sourceform; p; p = p->next)
 	    if (is_heading_type(p->type)) {
@@ -514,7 +533,7 @@ void html_backend(paragraph *sourceform, keywordlist *keywords,
 		    continue;
 		}
 
-		sect = html_new_sect(&sects, p);
+		sect = html_new_sect(&sects, p, &conf);
 		sect->text = p->next;
 
 		sect->contents_depth = contents_depth(conf, d+1) - (d+1);
@@ -528,23 +547,30 @@ void html_backend(paragraph *sourceform, keywordlist *keywords,
 
 		html_file_section(&conf, &files, sect, d);
 
-		sect->fragment = html_format(p, conf.template_fragment);
-		sect->fragment = html_sanitise_fragment(&files, sect->file,
-							sect->fragment);
+		{
+		    int i;
+		    for (i=0; i < conf.ntfragments; i++) {
+			sect->fragments[i] =
+			    html_format(p, conf.template_fragments[i]);
+			sect->fragments[i] =
+			    html_sanitise_fragment(&files, sect->file,
+						   sect->fragments[i]);
+		    }
+		}
 	    }
 
 	/* And the index, if we have one. */
 	has_index = (count234(idx->entries) > 0);
 	if (has_index) {
-	    sect = html_new_sect(&sects, NULL);
+	    sect = html_new_sect(&sects, NULL, &conf);
 	    sect->text = NULL;
 	    sect->type = INDEX;
 	    sect->parent = topsect;
             sect->contents_depth = 0;
 	    html_file_section(&conf, &files, sect, 0);   /* peer of chapters */
-	    sect->fragment = utoa_dup(conf.index_text, CS_ASCII);
-	    sect->fragment = html_sanitise_fragment(&files, sect->file,
-						    sect->fragment);
+	    sect->fragments[0] = utoa_dup(conf.index_text, CS_ASCII);
+	    sect->fragments[0] = html_sanitise_fragment(&files, sect->file,
+							sect->fragments[0]);
 	    files.index = sect->file;
 	}
     }
@@ -591,7 +617,7 @@ void html_backend(paragraph *sourceform, keywordlist *keywords,
 		 * won't attempt to add it to the contents or
 		 * anything weird like that).
 		 */
-		sect = html_new_sect(&nonsects, p);
+		sect = html_new_sect(&nonsects, p, &conf);
 		sect->file = parent->file;
 		sect->parent = parent;
 		p->private_data = sect;
@@ -600,11 +626,11 @@ void html_backend(paragraph *sourceform, keywordlist *keywords,
 		 * Fragment IDs for these paragraphs will simply be
 		 * `p' followed by an integer.
 		 */
-		sect->fragment = snewn(40, char);
-		sprintf(sect->fragment, "p%d",
+		sect->fragments[0] = snewn(40, char);
+		sprintf(sect->fragments[0], "p%d",
 			sect->file->last_fragment_number++);
-		sect->fragment = html_sanitise_fragment(&files, sect->file,
-							sect->fragment);
+		sect->fragments[0] = html_sanitise_fragment(&files, sect->file,
+							    sect->fragments[0]);
 	    }
 	}
     }
@@ -1060,14 +1086,18 @@ void html_backend(paragraph *sourceform, keywordlist *keywords,
 		    element_open(&ho, htag);
 
 		    /*
-		     * Provide anchor for cross-links to target.
+		     * Provide anchor(s) for cross-links to target.
 		     * 
 		     * (Also we'll have to do this separately in
 		     * other paragraph types - NumberedList and
 		     * BiblioCited.)
 		     */
-		    if (s->fragment)
-			html_fragment(&ho, s->fragment);
+		    {
+			int i;
+			for (i=0; i < conf.ntfragments; i++)
+			    if (s->fragments[i])
+				html_fragment(&ho, s->fragments[i]);
+		    }
 
 		    html_section_title(&ho, s, f, keywords, &conf, TRUE);
 
@@ -1199,7 +1229,10 @@ void html_backend(paragraph *sourceform, keywordlist *keywords,
 				element_open(&ho, "p");
 				if (p->private_data) {
 				    htmlsect *s = (htmlsect *)p->private_data;
-				    html_fragment(&ho, s->fragment);
+				    int i;
+				    for (i=0; i < conf.ntfragments; i++)
+					if (s->fragments[i])
+					    html_fragment(&ho, s->fragments[i]);
 				}
 				html_nl(&ho);
 				html_words(&ho, p->kwtext, ALL,
@@ -1215,7 +1248,10 @@ void html_backend(paragraph *sourceform, keywordlist *keywords,
 				element_open(&ho, "li");
 				if (p->private_data) {
 				    htmlsect *s = (htmlsect *)p->private_data;
-				    html_fragment(&ho, s->fragment);
+				    int i;
+				    for (i=0; i < conf.ntfragments; i++)
+					if (s->fragments[i])
+					    html_fragment(&ho, s->fragments[i]);
 				}
 				html_nl(&ho);
 				stackhead->itemtype = LI;
@@ -1429,12 +1465,6 @@ void html_backend(paragraph *sourceform, keywordlist *keywords,
     /*
      * Free all the working data.
      */
-    sfree(conf.asect);
-    sfree(conf.single_filename);
-    sfree(conf.contents_filename);
-    sfree(conf.index_filename);
-    sfree(conf.template_filename);
-    sfree(conf.template_fragment);
     {
 	htmlfragment *frag;
 	while ( (frag = (htmlfragment *)delpos234(files.frags, 0)) != NULL ) {
@@ -1451,15 +1481,21 @@ void html_backend(paragraph *sourceform, keywordlist *keywords,
 	htmlsect *sect, *tmp;
 	sect = sects.head;
 	while (sect) {
+	    int i;
 	    tmp = sect->next;
-	    sfree(sect->fragment);
+	    for (i=0; i < conf.ntfragments; i++)
+		sfree(sect->fragments[i]);
+	    sfree(sect->fragments);
 	    sfree(sect);
 	    sect = tmp;
 	}
 	sect = nonsects.head;
 	while (sect) {
+	    int i;
 	    tmp = sect->next;
-	    sfree(sect->fragment);
+	    for (i=0; i < conf.ntfragments; i++)
+		sfree(sect->fragments[i]);
+	    sfree(sect->fragments);
 	    sfree(sect);
 	    sect = tmp;
 	}
@@ -1494,6 +1530,14 @@ void html_backend(paragraph *sourceform, keywordlist *keywords,
 		    sfree(hr);
 		}
     }
+    sfree(conf.asect);
+    sfree(conf.single_filename);
+    sfree(conf.contents_filename);
+    sfree(conf.index_filename);
+    sfree(conf.template_filename);
+    while (conf.ntfragments--)
+	sfree(conf.template_fragments[conf.ntfragments]);
+    sfree(conf.template_fragments);
 }
 
 static void html_file_section(htmlconfig *cfg, htmlfilelist *files,
@@ -1591,7 +1635,8 @@ static htmlfile *html_new_file(htmlfilelist *list, char *filename)
     return ret;
 }
 
-static htmlsect *html_new_sect(htmlsectlist *list, paragraph *title)
+static htmlsect *html_new_sect(htmlsectlist *list, paragraph *title,
+			       htmlconfig *cfg)
 {
     htmlsect *ret = snew(htmlsect);
 
@@ -1607,6 +1652,13 @@ static htmlsect *html_new_sect(htmlsectlist *list, paragraph *title)
     ret->parent = NULL;
     ret->type = NORMAL;
 
+    ret->fragments = snewn(cfg->ntfragments, char *);
+    {
+	int i;
+	for (i=0; i < cfg->ntfragments; i++)
+	    ret->fragments[i] = NULL;
+    }
+
     return ret;
 }
 
@@ -1639,7 +1691,7 @@ static void html_words(htmloutput *ho, word *words, int flags,
 
 	    assert(s);
 
-	    html_href(ho, file, s->file, s->fragment);
+	    html_href(ho, file, s->file, s->fragments[0]);
 	}
 	break;
       case word_HyperEnd:
@@ -2047,6 +2099,13 @@ static char *html_sanitise_fragment(htmlfilelist *files, htmlfile *file,
 	*q = '\0';
     }
 
+    /* If there's nothing left, make something valid up */
+    if (!*text) {
+	static const char *anonfrag = "anon";
+	text = sresize(text, lenof(anonfrag), char);
+	strcpy(text, anonfrag);
+    }
+
     /*
      * Now we check for clashes with other fragment names, and
      * adjust this one if necessary by appending a hyphen followed
@@ -2102,7 +2161,7 @@ static void html_contents_entry(htmloutput *ho, int depth, htmlsect *s,
 	return;
 
     element_open(ho, "li");
-    html_href(ho, thisfile, s->file, s->fragment);
+    html_href(ho, thisfile, s->file, s->fragments[0]);
     html_section_title(ho, s, thisfile, keywords, cfg, FALSE);
     element_close(ho, "a");
     /* <li> will be closed by a later invocation */