Do not write duplicate id= attributes, they violate HTML syntax.

[mandoc.git] / html.c

diff --git a/html.c b/html.c
index 60e883710a2f85cf87372c40fe758e2a90cdbcd0..9ad83e8ec33606e48312b179fc0fa511e55c791a 100644 (file)
--- a/html.c
+++ b/html.c
@@ -1,4 +1,4 @@
-/*     $Id: html.c,v 1.228 2018/05/21 01:11:31 schwarze Exp $ */
+/*     $Id: html.c,v 1.229 2018/05/25 20:23:51 schwarze Exp $ */
 /*
  * Copyright (c) 2008-2011, 2014 Kristaps Dzonsons <kristaps@bsd.lv>
  * Copyright (c) 2011-2015, 2017, 2018 Ingo Schwarze <schwarze@openbsd.org>
@@ -22,6 +22,7 @@
 #include <assert.h>
 #include <ctype.h>
 #include <stdarg.h>
+#include <stddef.h>
 #include <stdio.h>
 #include <stdint.h>
 #include <stdlib.h>
@@ -29,6 +30,7 @@
 #include <unistd.h>
 
 #include "mandoc_aux.h"
+#include "mandoc_ohash.h"
 #include "mandoc.h"
 #include "roff.h"
 #include "out.h"
@@ -117,6 +119,9 @@ static      const char      *const roffscales[SCALE_MAX] = {
        "ex", /* SCALE_FS */
 };
 
+/* Avoid duplicate HTML id= attributes. */
+static struct ohash     id_unique;
+
 static void     a2width(const char *, struct roffsu *);
 static void     print_byte(struct html *, char);
 static void     print_endword(struct html *);
@@ -144,6 +149,8 @@ html_alloc(const struct manoutput *outopts)
        if (outopts->fragment)
                h->oflags |= HTML_FRAGMENT;
 
+       mandoc_ohash_init(&id_unique, 4, 0);
+
        return h;
 }
 
@@ -152,15 +159,22 @@ html_free(void *p)
 {
        struct tag      *tag;
        struct html     *h;
+       char            *cp;
+       unsigned int     slot;
 
        h = (struct html *)p;
-
        while ((tag = h->tag) != NULL) {
                h->tag = tag->next;
                free(tag);
        }
-
        free(h);
+
+       cp = ohash_first(&id_unique, &slot);
+       while (cp != NULL) {
+               free(cp);
+               cp = ohash_next(&id_unique, &slot);
+       }
+       ohash_delete(&id_unique);
 }
 
 void
@@ -257,10 +271,12 @@ print_metaf(struct html *h, enum mandoc_esc deco)
 }
 
 char *
-html_make_id(const struct roff_node *n)
+html_make_id(const struct roff_node *n, int unique)
 {
        const struct roff_node  *nch;
-       char                    *buf, *cp;
+       char                    *buf, *bufs, *cp;
+       unsigned int             slot;
+       int                      suffix;
 
        for (nch = n->child; nch != NULL; nch = nch->next)
                if (nch->type != ROFFT_TEXT)
@@ -277,6 +293,30 @@ html_make_id(const struct roff_node *n)
                if (*cp == ' ')
                        *cp = '_';
 
+       if (unique == 0)
+               return buf;
+
+       /* Avoid duplicate HTML id= attributes. */
+
+       bufs = NULL;
+       suffix = 1;
+       slot = ohash_qlookup(&id_unique, buf);
+       cp = ohash_find(&id_unique, slot);
+       if (cp != NULL) {
+               while (cp != NULL) {
+                       free(bufs);
+                       if (++suffix > 127) {
+                               free(buf);
+                               return NULL;
+                       }
+                       mandoc_asprintf(&bufs, "%s_%d", buf, suffix);
+                       slot = ohash_qlookup(&id_unique, bufs);
+                       cp = ohash_find(&id_unique, slot);
+               }
+               free(buf);
+               buf = bufs;
+       }
+       ohash_insert(&id_unique, slot, buf);
        return buf;
 }