[svn] Don't descend into HTML that was downloaded by following <img src=...>

[wget] / src / html-url.c

diff --git a/src/html-url.c b/src/html-url.c
index 80f5b96c19ffcec006a0f9d3565868ddd11be95a..c2ed2c588c26f27355e2864e42838165a81bdde6 100644 (file)
--- a/src/html-url.c
+++ b/src/html-url.c
@@ -121,11 +121,19 @@ static struct known_tag {
 /* tag_url_attributes documents which attributes of which tags contain
    URLs to harvest.  It is used by tag_find_urls.  */
 
-/* Defines for the FLAGS field; currently only one flag is defined. */
+/* Defines for the FLAGS. */
 
-/* This tag points to an external document not necessary for rendering this 
-   document (i.e. it's not an inlined image, stylesheet, etc.). */
-#define TUA_EXTERNAL 1
+/* The link is "inline", i.e. needs to be retrieved for this document
+   to be correctly rendered.  Inline links include inlined images,
+   stylesheets, children frames, etc.  */
+#define ATTR_INLINE    1
+
+/* The link is expected to yield HTML contents.  It's important not to
+   try to follow HTML obtained by following e.g. <img src="...">
+   regardless of content-type.  Doing this causes infinite loops for
+   "images" that return non-404 error pages with links to the same
+   image.  */
+#define ATTR_HTML      2
 
 /* For tags handled by tag_find_urls: attributes that contain URLs to
    download. */
@@ -134,26 +142,26 @@ static struct {
   const char *attr_name;
   int flags;
 } tag_url_attributes[] = {
-  { TAG_A,             "href",         TUA_EXTERNAL },
-  { TAG_APPLET,                "code",         0 },
-  { TAG_AREA,          "href",         TUA_EXTERNAL },
-  { TAG_BGSOUND,       "src",          0 },
-  { TAG_BODY,          "background",   0 },
-  { TAG_EMBED,         "href",         TUA_EXTERNAL },
-  { TAG_EMBED,         "src",          0 },
-  { TAG_FIG,           "src",          0 },
-  { TAG_FRAME,         "src",          0 },
-  { TAG_IFRAME,                "src",          0 },
-  { TAG_IMG,           "href",         0 },
-  { TAG_IMG,           "lowsrc",       0 },
-  { TAG_IMG,           "src",          0 },
-  { TAG_INPUT,         "src",          0 },
-  { TAG_LAYER,         "src",          0 },
-  { TAG_OVERLAY,       "src",          0 },
-  { TAG_SCRIPT,                "src",          0 },
-  { TAG_TABLE,         "background",   0 },
-  { TAG_TD,            "background",   0 },
-  { TAG_TH,            "background",   0 }
+  { TAG_A,             "href",         ATTR_HTML },
+  { TAG_APPLET,                "code",         ATTR_INLINE },
+  { TAG_AREA,          "href",         ATTR_HTML },
+  { TAG_BGSOUND,       "src",          ATTR_INLINE },
+  { TAG_BODY,          "background",   ATTR_INLINE },
+  { TAG_EMBED,         "href",         ATTR_HTML },
+  { TAG_EMBED,         "src",          ATTR_INLINE | ATTR_HTML },
+  { TAG_FIG,           "src",          ATTR_INLINE },
+  { TAG_FRAME,         "src",          ATTR_INLINE | ATTR_HTML },
+  { TAG_IFRAME,                "src",          ATTR_INLINE | ATTR_HTML },
+  { TAG_IMG,           "href",         ATTR_INLINE },
+  { TAG_IMG,           "lowsrc",       ATTR_INLINE },
+  { TAG_IMG,           "src",          ATTR_INLINE },
+  { TAG_INPUT,         "src",          ATTR_INLINE },
+  { TAG_LAYER,         "src",          ATTR_INLINE | ATTR_HTML },
+  { TAG_OVERLAY,       "src",          ATTR_INLINE | ATTR_HTML },
+  { TAG_SCRIPT,                "src",          ATTR_INLINE },
+  { TAG_TABLE,         "background",   ATTR_INLINE },
+  { TAG_TD,            "background",   ATTR_INLINE },
+  { TAG_TH,            "background",   ATTR_INLINE }
 };
 
 /* The lists of interesting tags and attributes are built dynamically,
@@ -262,7 +270,7 @@ struct map_context {
    size.  */
 
 static struct urlpos *
-append_one_url (const char *link_uri, int inlinep,
+append_one_url (const char *link_uri,
                struct taginfo *tag, int attrind, struct map_context *ctx)
 {
   int link_has_scheme = url_has_scheme (link_uri);
@@ -326,7 +334,6 @@ append_one_url (const char *link_uri, int inlinep,
   newel->url = url;
   newel->pos = tag->attrs[attrind].value_raw_beginning - ctx->text;
   newel->size = tag->attrs[attrind].value_raw_size;
-  newel->link_inline_p = inlinep;
 
   /* A URL is relative if the host is not named, and the name does not
      start with `/'.  */
@@ -393,8 +400,15 @@ tag_find_urls (int tagid, struct taginfo *tag, struct map_context *ctx)
          if (0 == strcasecmp (tag->attrs[attrind].name,
                               tag_url_attributes[i].attr_name))
            {
-             int flags = tag_url_attributes[i].flags;
-             append_one_url (link, !(flags & TUA_EXTERNAL), tag, attrind, ctx);
+             struct urlpos *up = append_one_url (link, tag, attrind, ctx);
+             if (up)
+               {
+                 int flags = tag_url_attributes[i].flags;
+                 if (flags & ATTR_INLINE)
+                   up->link_inline_p = 1;
+                 if (flags & ATTR_HTML)
+                   up->link_expect_html = 1;
+               }
            }
        }
     }
@@ -411,7 +425,7 @@ tag_handle_base (int tagid, struct taginfo *tag, struct map_context *ctx)
   if (!newbase)
     return;
 
-  base_urlpos = append_one_url (newbase, 0, tag, attrind, ctx);
+  base_urlpos = append_one_url (newbase, tag, attrind, ctx);
   if (!base_urlpos)
     return;
   base_urlpos->ignore_when_downloading = 1;
@@ -434,10 +448,9 @@ tag_handle_form (int tagid, struct taginfo *tag, struct map_context *ctx)
   char *action = find_attr (tag, "action", &attrind);
   if (action)
     {
-      struct urlpos *action_urlpos = append_one_url (action, 0, tag,
-                                                    attrind, ctx);
-      if (action_urlpos)
-       action_urlpos->ignore_when_downloading = 1;
+      struct urlpos *up = append_one_url (action, tag, attrind, ctx);
+      if (up)
+       up->ignore_when_downloading = 1;
     }
 }
 
@@ -458,11 +471,15 @@ tag_handle_link (int tagid, struct taginfo *tag, struct map_context *ctx)
   */
   if (href)
     {
-      char *rel  = find_attr (tag, "rel", NULL);
-      int inlinep = (rel
-                    && (0 == strcasecmp (rel, "stylesheet")
-                        || 0 == strcasecmp (rel, "shortcut icon")));
-      append_one_url (href, inlinep, tag, attrind, ctx);
+      struct urlpos *up = append_one_url (href, tag, attrind, ctx);
+      if (up)
+       {
+         char *rel = find_attr (tag, "rel", NULL);
+         if (rel
+             && (0 == strcasecmp (rel, "stylesheet")
+                 || 0 == strcasecmp (rel, "shortcut icon")))
+           up->link_inline_p = 1;
+       }
     }
 }
 
@@ -511,7 +528,7 @@ tag_handle_meta (int tagid, struct taginfo *tag, struct map_context *ctx)
       while (ISSPACE (*p))
        ++p;
 
-      entry = append_one_url (p, 0, tag, attrind, ctx);
+      entry = append_one_url (p, tag, attrind, ctx);
       if (entry)
        {
          entry->link_refresh_p = 1;