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diff --git a/src/recur.c b/src/recur.c
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+++ b/src/recur.c
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+/* Handling of recursive HTTP retrieving.
+ Copyright (C) 1996-2012, 2015, 2018-2022 Free Software Foundation,
+ Inc.
+
+This file is part of GNU Wget.
+
+GNU Wget 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.
+
+GNU Wget 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 Wget. If not, see <http://www.gnu.org/licenses/>.
+
+Additional permission under GNU GPL version 3 section 7
+
+If you modify this program, or any covered work, by linking or
+combining it with the OpenSSL project's OpenSSL library (or a
+modified version of that library), containing parts covered by the
+terms of the OpenSSL or SSLeay licenses, the Free Software Foundation
+grants you additional permission to convey the resulting work.
+Corresponding Source for a non-source form of such a combination
+shall include the source code for the parts of OpenSSL used as well
+as that of the covered work. */
+
+#include "wget.h"
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <errno.h>
+#include <assert.h>
+
+#include "url.h"
+#include "recur.h"
+#include "utils.h"
+#include "retr.h"
+#include "ftp.h"
+#include "host.h"
+#include "hash.h"
+#include "res.h"
+#include "convert.h"
+#include "html-url.h"
+#include "css-url.h"
+#include "spider.h"
+#include "exits.h"
+
+/* Functions for maintaining the URL queue. */
+
+struct queue_element {
+ const char *url; /* the URL to download */
+ const char *referer; /* the referring document */
+ int depth; /* the depth */
+ bool html_allowed; /* whether the document is allowed to
+ be treated as HTML. */
+ struct iri *iri; /* sXXXav */
+ bool css_allowed; /* whether the document is allowed to
+ be treated as CSS. */
+ struct queue_element *next; /* next element in queue */
+};
+
+struct url_queue {
+ struct queue_element *head;
+ struct queue_element *tail;
+ int count, maxcount;
+};
+
+/* Create a URL queue. */
+
+static struct url_queue *
+url_queue_new (void)
+{
+ struct url_queue *queue = xnew0 (struct url_queue);
+ return queue;
+}
+
+/* Delete a URL queue. */
+
+static void
+url_queue_delete (struct url_queue *queue)
+{
+ xfree (queue);
+}
+
+/* Enqueue a URL in the queue. The queue is FIFO: the items will be
+ retrieved ("dequeued") from the queue in the order they were placed
+ into it. */
+
+static void
+url_enqueue (struct url_queue *queue, struct iri *i,
+ const char *url, const char *referer, int depth,
+ bool html_allowed, bool css_allowed)
+{
+ struct queue_element *qel = xnew (struct queue_element);
+ qel->iri = i;
+ qel->url = url;
+ qel->referer = referer;
+ qel->depth = depth;
+ qel->html_allowed = html_allowed;
+ qel->css_allowed = css_allowed;
+ qel->next = NULL;
+
+ ++queue->count;
+ if (queue->count > queue->maxcount)
+ queue->maxcount = queue->count;
+
+ DEBUGP (("Enqueuing %s at depth %d\n",
+ quotearg_n_style (0, escape_quoting_style, url), depth));
+ DEBUGP (("Queue count %d, maxcount %d.\n", queue->count, queue->maxcount));
+
+ if (i)
+ DEBUGP (("[IRI Enqueuing %s with %s\n", quote_n (0, url),
+ i->uri_encoding ? quote_n (1, i->uri_encoding) : "None"));
+
+ if (queue->tail)
+ queue->tail->next = qel;
+ queue->tail = qel;
+
+ if (!queue->head)
+ queue->head = queue->tail;
+}
+
+/* Take a URL out of the queue. Return true if this operation
+ succeeded, or false if the queue is empty. */
+
+static bool
+url_dequeue (struct url_queue *queue, struct iri **i,
+ const char **url, const char **referer, int *depth,
+ bool *html_allowed, bool *css_allowed)
+{
+ struct queue_element *qel = queue->head;
+
+ if (!qel)
+ return false;
+
+ queue->head = queue->head->next;
+ if (!queue->head)
+ queue->tail = NULL;
+
+ *i = qel->iri;
+ *url = qel->url;
+ *referer = qel->referer;
+ *depth = qel->depth;
+ *html_allowed = qel->html_allowed;
+ *css_allowed = qel->css_allowed;
+
+ --queue->count;
+
+ DEBUGP (("Dequeuing %s at depth %d\n",
+ quotearg_n_style (0, escape_quoting_style, qel->url), qel->depth));
+ DEBUGP (("Queue count %d, maxcount %d.\n", queue->count, queue->maxcount));
+
+ xfree (qel);
+ return true;
+}
+
+static void blacklist_add (struct hash_table *blacklist, const char *url)
+{
+ char *url_unescaped = xstrdup (url);
+
+ url_unescape (url_unescaped);
+ string_set_add (blacklist, url_unescaped);
+ xfree (url_unescaped);
+}
+
+static int blacklist_contains (struct hash_table *blacklist, const char *url)
+{
+ char *url_unescaped = xstrdup(url);
+ int ret;
+
+ url_unescape (url_unescaped);
+ ret = string_set_contains (blacklist, url_unescaped);
+ xfree (url_unescaped);
+
+ return ret;
+}
+
+typedef enum
+{
+ WG_RR_SUCCESS, WG_RR_BLACKLIST, WG_RR_NOTHTTPS, WG_RR_NONHTTP, WG_RR_ABSOLUTE,
+ WG_RR_DOMAIN, WG_RR_PARENT, WG_RR_LIST, WG_RR_REGEX, WG_RR_RULES,
+ WG_RR_SPANNEDHOST, WG_RR_ROBOTS
+} reject_reason;
+
+static reject_reason download_child (const struct urlpos *, struct url *, int,
+ struct url *, struct hash_table *, struct iri *);
+static reject_reason descend_redirect (const char *, struct url *, int,
+ struct url *, struct hash_table *, struct iri *);
+static void write_reject_log_header (FILE *);
+static void write_reject_log_reason (FILE *, reject_reason,
+ const struct url *, const struct url *);
+
+/* Retrieve a part of the web beginning with START_URL. This used to
+ be called "recursive retrieval", because the old function was
+ recursive and implemented depth-first search. retrieve_tree on the
+ other hand implements breadth-search traversal of the tree, which
+ results in much nicer ordering of downloads.
+
+ The algorithm this function uses is simple:
+
+ 1. put START_URL in the queue.
+ 2. while there are URLs in the queue:
+
+ 3. get next URL from the queue.
+ 4. download it.
+ 5. if the URL is HTML and its depth does not exceed maximum depth,
+ get the list of URLs embedded therein.
+ 6. for each of those URLs do the following:
+
+ 7. if the URL is not one of those downloaded before, and if it
+ satisfies the criteria specified by the various command-line
+ options, add it to the queue. */
+
+uerr_t
+retrieve_tree (struct url *start_url_parsed, struct iri *pi)
+{
+ uerr_t status = RETROK;
+
+ /* The queue of URLs we need to load. */
+ struct url_queue *queue;
+
+ /* The URLs we do not wish to enqueue, because they are already in
+ the queue, but haven't been downloaded yet. */
+ struct hash_table *blacklist;
+
+ struct iri *i = iri_new ();
+
+ FILE *rejectedlog = NULL; /* Don't write a rejected log. */
+
+ /* Duplicate pi struct if not NULL */
+ if (pi)
+ {
+#define COPYSTR(x) (x) ? xstrdup(x) : NULL;
+ i->uri_encoding = COPYSTR (pi->uri_encoding);
+ i->content_encoding = COPYSTR (pi->content_encoding);
+ i->utf8_encode = pi->utf8_encode;
+#undef COPYSTR
+ }
+#ifdef ENABLE_IRI
+ else
+ set_uri_encoding (i, opt.locale, true);
+#endif
+
+ queue = url_queue_new ();
+ blacklist = make_string_hash_table (0);
+
+ /* Enqueue the starting URL. Use start_url_parsed->url rather than
+ just URL so we enqueue the canonical form of the URL. */
+ url_enqueue (queue, i, xstrdup (start_url_parsed->url), NULL, 0, true,
+ false);
+ blacklist_add (blacklist, start_url_parsed->url);
+
+ if (opt.rejected_log)
+ {
+ rejectedlog = fopen (opt.rejected_log, "w");
+ write_reject_log_header (rejectedlog);
+ if (!rejectedlog)
+ logprintf (LOG_NOTQUIET, "%s: %s\n", opt.rejected_log, strerror (errno));
+ }
+
+ while (1)
+ {
+ bool descend = false;
+ char *url, *referer, *file = NULL;
+ int depth;
+ bool html_allowed, css_allowed;
+ bool is_css = false;
+ bool dash_p_leaf_HTML = false;
+
+ if (opt.quota && total_downloaded_bytes > opt.quota)
+ break;
+ if (status == FWRITEERR)
+ break;
+
+ /* Get the next URL from the queue... */
+
+ if (!url_dequeue (queue, (struct iri **) &i,
+ (const char **)&url, (const char **)&referer,
+ &depth, &html_allowed, &css_allowed))
+ break;
+
+ /* ...and download it. Note that this download is in most cases
+ unconditional, as download_child already makes sure a file
+ doesn't get enqueued twice -- and yet this check is here, and
+ not in download_child. This is so that if you run `wget -r
+ URL1 URL2', and a random URL is encountered once under URL1
+ and again under URL2, but at a different (possibly smaller)
+ depth, we want the URL's children to be taken into account
+ the second time. */
+ if (dl_url_file_map && hash_table_contains (dl_url_file_map, url))
+ {
+ bool is_css_bool;
+
+ file = xstrdup (hash_table_get (dl_url_file_map, url));
+
+ DEBUGP (("Already downloaded \"%s\", reusing it from \"%s\".\n",
+ url, file));
+
+ if ((is_css_bool = (css_allowed
+ && downloaded_css_set
+ && string_set_contains (downloaded_css_set, file)))
+ || (html_allowed
+ && downloaded_html_set
+ && string_set_contains (downloaded_html_set, file)))
+ {
+ descend = true;
+ is_css = is_css_bool;
+ }
+ }
+ else
+ {
+ int dt = 0, url_err;
+ char *redirected = NULL;
+ struct url *url_parsed = url_parse (url, &url_err, i, true);
+
+ if (!url_parsed)
+ {
+ char *error = url_error (url, url_err);
+ logprintf (LOG_NOTQUIET, "%s: %s.\n",url, error);
+ xfree (error);
+ inform_exit_status (URLERROR);
+ }
+ else
+ {
+
+ status = retrieve_url (url_parsed, url, &file, &redirected, referer,
+ &dt, false, i, true);
+
+ if (html_allowed && file && status == RETROK
+ && (dt & RETROKF) && (dt & TEXTHTML))
+ {
+ descend = true;
+ is_css = false;
+ }
+
+ /* a little different, css_allowed can override content type
+ lots of web servers serve css with an incorrect content type
+ */
+ if (file && status == RETROK
+ && (dt & RETROKF) &&
+ ((dt & TEXTCSS) || css_allowed))
+ {
+ descend = true;
+ is_css = true;
+ }
+
+ if (redirected)
+ {
+ /* We have been redirected, possibly to another host, or
+ different path, or wherever. Check whether we really
+ want to follow it. */
+ if (descend)
+ {
+ reject_reason r = descend_redirect (redirected, url_parsed,
+ depth, start_url_parsed, blacklist, i);
+ if (r == WG_RR_SUCCESS)
+ {
+ /* Make sure that the old pre-redirect form gets
+ blacklisted. */
+ blacklist_add (blacklist, url);
+ }
+ else
+ {
+ write_reject_log_reason (rejectedlog, r, url_parsed, start_url_parsed);
+ descend = false;
+ }
+ }
+
+ xfree (url);
+ url = redirected;
+ }
+ else
+ {
+ xfree (url);
+ url = xstrdup (url_parsed->url);
+ }
+ url_free (url_parsed);
+ }
+ }
+
+ if (opt.spider)
+ {
+ visited_url (url, referer);
+ }
+
+ if (descend
+ && depth >= opt.reclevel && opt.reclevel != INFINITE_RECURSION)
+ {
+ if (opt.page_requisites
+ && (depth == opt.reclevel || depth == opt.reclevel + 1))
+ {
+ /* When -p is specified, we are allowed to exceed the
+ maximum depth, but only for the "inline" links,
+ i.e. those that are needed to display the page.
+ Originally this could exceed the depth at most by
+ one, but we allow one more level so that the leaf
+ pages that contain frames can be loaded
+ correctly. */
+ dash_p_leaf_HTML = true;
+ }
+ else
+ {
+ /* Either -p wasn't specified or it was and we've
+ already spent the two extra (pseudo-)levels that it
+ affords us, so we need to bail out. */
+ DEBUGP (("Not descending further; at depth %d, max. %d.\n",
+ depth, opt.reclevel));
+ descend = false;
+ }
+ }
+
+ /* If the downloaded document was HTML or CSS, parse it and enqueue the
+ links it contains. */
+
+ if (descend)
+ {
+ bool meta_disallow_follow = false;
+ struct urlpos *children
+ = is_css ? get_urls_css_file (file, url) :
+ get_urls_html (file, url, &meta_disallow_follow, i);
+
+ if (opt.use_robots && meta_disallow_follow)
+ {
+ logprintf(LOG_VERBOSE, _("nofollow attribute found in %s. Will not follow any links on this page\n"), file);
+ free_urlpos (children);
+ children = NULL;
+ }
+
+ if (children)
+ {
+ struct urlpos *child = children;
+ struct url *url_parsed = url_parse (url, NULL, i, true);
+ struct iri *ci;
+ char *referer_url = url;
+ bool strip_auth;
+
+ assert (url_parsed != NULL);
+
+ if (!url_parsed)
+ continue;
+
+ strip_auth = (url_parsed && url_parsed->user);
+
+ /* Strip auth info if present */
+ if (strip_auth)
+ referer_url = url_string (url_parsed, URL_AUTH_HIDE);
+
+ for (; child; child = child->next)
+ {
+ reject_reason r;
+
+ if (child->ignore_when_downloading)
+ {
+ DEBUGP (("Not following due to 'ignore' flag: %s\n", child->url->url));
+ continue;
+ }
+
+ if (dash_p_leaf_HTML && !child->link_inline_p)
+ {
+ DEBUGP (("Not following due to 'link inline' flag: %s\n", child->url->url));
+ continue;
+ }
+
+ r = download_child (child, url_parsed, depth,
+ start_url_parsed, blacklist, i);
+ if (r == WG_RR_SUCCESS)
+ {
+ ci = iri_new ();
+ set_uri_encoding (ci, i->content_encoding, false);
+ url_enqueue (queue, ci, xstrdup (child->url->url),
+ xstrdup (referer_url), depth + 1,
+ child->link_expect_html,
+ child->link_expect_css);
+ /* We blacklist the URL we have enqueued, because we
+ don't want to enqueue (and hence download) the
+ same URL twice. */
+ blacklist_add (blacklist, child->url->url);
+ }
+ else
+ {
+ write_reject_log_reason (rejectedlog, r, child->url, url_parsed);
+ }
+ }
+
+ if (strip_auth)
+ xfree (referer_url);
+ url_free (url_parsed);
+ free_urlpos (children);
+ }
+ }
+
+ if (file
+ && (opt.delete_after
+ || opt.spider /* opt.recursive is implicitly true */
+ || !acceptable (file)))
+ {
+ /* Either --delete-after was specified, or we loaded this
+ (otherwise unneeded because of --spider or rejected by -R)
+ HTML file just to harvest its hyperlinks -- in either case,
+ delete the local file. */
+ DEBUGP (("Removing file due to %s in recursive_retrieve():\n",
+ opt.delete_after ? "--delete-after" :
+ (opt.spider ? "--spider" :
+ "recursive rejection criteria")));
+ logprintf (LOG_VERBOSE,
+ (opt.delete_after || opt.spider
+ ? _("Removing %s.\n")
+ : _("Removing %s since it should be rejected.\n")),
+ file);
+ if (unlink (file))
+ logprintf (LOG_NOTQUIET, "unlink: %s\n", strerror (errno));
+ logputs (LOG_VERBOSE, "\n");
+ register_delete_file (file);
+ }
+
+ xfree (url);
+ xfree (referer);
+ xfree (file);
+ iri_free (i);
+ }
+
+ if (rejectedlog)
+ {
+ fclose (rejectedlog);
+ rejectedlog = NULL;
+ }
+
+ /* If anything is left of the queue due to a premature exit, free it
+ now. */
+ {
+ char *d1, *d2;
+ int d3;
+ bool d4, d5;
+ struct iri *d6;
+ while (url_dequeue (queue, (struct iri **)&d6,
+ (const char **)&d1, (const char **)&d2, &d3, &d4, &d5))
+ {
+ iri_free (d6);
+ xfree (d1);
+ xfree (d2);
+ }
+ }
+ url_queue_delete (queue);
+
+ string_set_free (blacklist);
+
+ if (opt.quota && total_downloaded_bytes > opt.quota)
+ return QUOTEXC;
+ else if (status == FWRITEERR)
+ return FWRITEERR;
+ else
+ return RETROK;
+}
+
+/* Based on the context provided by retrieve_tree, decide whether a
+ URL is to be descended to. This is only ever called from
+ retrieve_tree, but is in a separate function for clarity.
+
+ The most expensive checks (such as those for robots) are memoized
+ by storing these URLs to BLACKLIST. This may or may not help. It
+ will help if those URLs are encountered many times. */
+
+static reject_reason
+download_child (const struct urlpos *upos, struct url *parent, int depth,
+ struct url *start_url_parsed, struct hash_table *blacklist,
+ struct iri *iri)
+{
+ struct url *u = upos->url;
+ const char *url = u->url;
+ bool u_scheme_like_http;
+ reject_reason reason = WG_RR_SUCCESS;
+
+ DEBUGP (("Deciding whether to enqueue \"%s\".\n", url));
+
+ if (blacklist_contains (blacklist, url))
+ {
+ if (opt.spider)
+ {
+ char *referrer = url_string (parent, URL_AUTH_HIDE_PASSWD);
+ DEBUGP (("download_child: parent->url is: %s\n", quote (parent->url)));
+ visited_url (url, referrer);
+ xfree (referrer);
+ }
+ DEBUGP (("Already on the black list.\n"));
+ reason = WG_RR_BLACKLIST;
+ goto out;
+ }
+
+ /* Several things to check for:
+ 1. if scheme is not https and https_only requested
+ 2. if scheme is not http, and we don't load it
+ 3. check for relative links (if relative_only is set)
+ 4. check for domain
+ 5. check for no-parent
+ 6. check for excludes && includes
+ 7. check for suffix
+ 8. check for same host (if spanhost is unset), with possible
+ gethostbyname baggage
+ 9. check for robots.txt
+
+ Addendum: If the URL is FTP, and it is to be loaded, only the
+ domain and suffix settings are "stronger".
+
+ Note that .html files will get loaded regardless of suffix rules
+ (but that is remedied later with unlink) unless the depth equals
+ the maximum depth.
+
+ More time- and memory- consuming tests should be put later on
+ the list. */
+
+#ifdef HAVE_SSL
+ if (opt.https_only && u->scheme != SCHEME_HTTPS)
+ {
+ DEBUGP (("Not following non-HTTPS links.\n"));
+ reason = WG_RR_NOTHTTPS;
+ goto out;
+ }
+#endif
+
+ /* Determine whether URL under consideration has a HTTP-like scheme. */
+ u_scheme_like_http = schemes_are_similar_p (u->scheme, SCHEME_HTTP);
+
+ /* 1. Schemes other than HTTP are normally not recursed into. */
+ if (!u_scheme_like_http && !((u->scheme == SCHEME_FTP
+#ifdef HAVE_SSL
+ || u->scheme == SCHEME_FTPS
+#endif
+ ) && opt.follow_ftp))
+ {
+ DEBUGP (("Not following non-HTTP schemes.\n"));
+ reason = WG_RR_NONHTTP;
+ goto out;
+ }
+
+ /* 2. If it is an absolute link and they are not followed, throw it
+ out. */
+ if (u_scheme_like_http)
+ if (opt.relative_only && !upos->link_relative_p)
+ {
+ DEBUGP (("It doesn't really look like a relative link.\n"));
+ reason = WG_RR_ABSOLUTE;
+ goto out;
+ }
+
+ /* 3. If its domain is not to be accepted/looked-up, chuck it
+ out. */
+ if (!accept_domain (u))
+ {
+ DEBUGP (("The domain was not accepted.\n"));
+ reason = WG_RR_DOMAIN;
+ goto out;
+ }
+
+ /* 4. Check for parent directory.
+
+ If we descended to a different host or changed the scheme, ignore
+ opt.no_parent. Also ignore it for documents needed to display
+ the parent page when in -p mode. */
+ if (opt.no_parent
+ && schemes_are_similar_p (u->scheme, start_url_parsed->scheme)
+ && 0 == strcasecmp (u->host, start_url_parsed->host)
+ && (u->scheme != start_url_parsed->scheme
+ || u->port == start_url_parsed->port)
+ && !(opt.page_requisites && upos->link_inline_p))
+ {
+ if (!subdir_p (start_url_parsed->dir, u->dir))
+ {
+ DEBUGP (("Going to \"%s\" would escape \"%s\" with no_parent on.\n",
+ u->dir, start_url_parsed->dir));
+ reason = WG_RR_PARENT;
+ goto out;
+ }
+ }
+
+ /* 5. If the file does not match the acceptance list, or is on the
+ rejection list, chuck it out. The same goes for the directory
+ exclusion and inclusion lists. */
+ if (opt.includes || opt.excludes)
+ {
+ if (!accdir (u->dir))
+ {
+ DEBUGP (("%s (%s) is excluded/not-included.\n", url, u->dir));
+ reason = WG_RR_LIST;
+ goto out;
+ }
+ }
+ if (!accept_url (url))
+ {
+ DEBUGP (("%s is excluded/not-included through regex.\n", url));
+ reason = WG_RR_REGEX;
+ goto out;
+ }
+
+ /* 6. Check for acceptance/rejection rules. We ignore these rules
+ for directories (no file name to match) and for non-leaf HTMLs,
+ which can lead to other files that do need to be downloaded. (-p
+ automatically implies non-leaf because with -p we can, if
+ necessary, overstep the maximum depth to get the page requisites.) */
+ if (u->file[0] != '\0'
+ && !(has_html_suffix_p (u->file)
+ /* The exception only applies to non-leaf HTMLs (but -p
+ always implies non-leaf because we can overstep the
+ maximum depth to get the requisites): */
+ && (/* non-leaf */
+ opt.reclevel == INFINITE_RECURSION
+ /* also non-leaf */
+ || depth < opt.reclevel - 1
+ /* -p, which implies non-leaf (see above) */
+ || opt.page_requisites)))
+ {
+ if (!acceptable (u->file))
+ {
+ DEBUGP (("%s (%s) does not match acc/rej rules.\n",
+ url, u->file));
+ reason = WG_RR_RULES;
+ goto out;
+ }
+ }
+
+ /* 7. */
+ if (schemes_are_similar_p (u->scheme, parent->scheme))
+ if (!opt.spanhost && 0 != strcasecmp (parent->host, u->host))
+ {
+ DEBUGP (("This is not the same hostname as the parent's (%s and %s).\n",
+ u->host, parent->host));
+ reason = WG_RR_SPANNEDHOST;
+ goto out;
+ }
+
+ /* 8. */
+ if (opt.use_robots && u_scheme_like_http)
+ {
+ struct robot_specs *specs = res_get_specs (u->host, u->port);
+ if (!specs)
+ {
+ char *rfile;
+ if (res_retrieve_file (url, &rfile, iri))
+ {
+ specs = res_parse_from_file (rfile);
+
+ /* Delete the robots.txt file if we chose to either delete the
+ files after downloading or we're just running a spider or
+ we use page requisites or pattern matching. */
+ if (opt.delete_after || opt.spider || match_tail(rfile, ".tmp", false))
+ {
+ logprintf (LOG_VERBOSE, _("Removing %s.\n"), rfile);
+ if (unlink (rfile))
+ logprintf (LOG_NOTQUIET, "unlink: %s\n",
+ strerror (errno));
+ }
+
+ xfree (rfile);
+ }
+ else
+ {
+ /* If we cannot get real specs, at least produce
+ dummy ones so that we can register them and stop
+ trying to retrieve them. */
+ specs = res_parse ("", 0);
+ }
+ res_register_specs (u->host, u->port, specs);
+ }
+
+ /* Now that we have (or don't have) robots.txt specs, we can
+ check what they say. */
+ if (!res_match_path (specs, u->path))
+ {
+ DEBUGP (("Not following %s because robots.txt forbids it.\n", url));
+ blacklist_add (blacklist, url);
+ reason = WG_RR_ROBOTS;
+ goto out;
+ }
+ }
+
+ out:
+
+ if (reason == WG_RR_SUCCESS)
+ /* The URL has passed all the tests. It can be placed in the
+ download queue. */
+ DEBUGP (("Decided to load it.\n"));
+ else
+ DEBUGP (("Decided NOT to load it.\n"));
+
+ return reason;
+}
+
+/* This function determines whether we will consider downloading the
+ children of a URL whose download resulted in a redirection,
+ possibly to another host, etc. It is needed very rarely, and thus
+ it is merely a simple-minded wrapper around download_child. */
+
+static reject_reason
+descend_redirect (const char *redirected, struct url *orig_parsed, int depth,
+ struct url *start_url_parsed, struct hash_table *blacklist,
+ struct iri *iri)
+{
+ struct url *new_parsed;
+ struct urlpos *upos;
+ reject_reason reason;
+
+ assert (orig_parsed != NULL);
+
+ new_parsed = url_parse (redirected, NULL, NULL, false);
+ assert (new_parsed != NULL);
+
+ upos = xnew0 (struct urlpos);
+ upos->url = new_parsed;
+
+ reason = download_child (upos, orig_parsed, depth,
+ start_url_parsed, blacklist, iri);
+
+ if (reason == WG_RR_SUCCESS)
+ blacklist_add (blacklist, upos->url->url);
+ else if (reason == WG_RR_LIST || reason == WG_RR_REGEX)
+ {
+ DEBUGP (("Ignoring decision for redirects, decided to load it.\n"));
+ blacklist_add (blacklist, upos->url->url);
+ reason = WG_RR_SUCCESS;
+ }
+ else
+ DEBUGP (("Redirection \"%s\" failed the test.\n", redirected));
+
+ url_free (new_parsed);
+ xfree (upos);
+
+ return reason;
+}
+
+
+/* This function writes the rejected log header. */
+static void
+write_reject_log_header (FILE *f)
+{
+ if (!f)
+ return;
+
+ /* Note: Update this header when columns change in any way. */
+ fprintf (f, "REASON\t"
+ "U_URL\tU_SCHEME\tU_HOST\tU_PORT\tU_PATH\tU_PARAMS\tU_QUERY\tU_FRAGMENT\t"
+ "P_URL\tP_SCHEME\tP_HOST\tP_PORT\tP_PATH\tP_PARAMS\tP_QUERY\tP_FRAGMENT\n");
+}
+
+/* This function writes a URL to the reject log. Internal use only. */
+static void
+write_reject_log_url (FILE *fp, const struct url *url)
+{
+ const char *escaped_str;
+ const char *scheme_str;
+
+ if (!fp)
+ return;
+
+ escaped_str = url_escape (url->url);
+
+ switch (url->scheme)
+ {
+ case SCHEME_HTTP: scheme_str = "SCHEME_HTTP"; break;
+#ifdef HAVE_SSL
+ case SCHEME_HTTPS: scheme_str = "SCHEME_HTTPS"; break;
+ case SCHEME_FTPS: scheme_str = "SCHEME_FTPS"; break;
+#endif
+ case SCHEME_FTP: scheme_str = "SCHEME_FTP"; break;
+ default: scheme_str = "SCHEME_INVALID"; break;
+ }
+
+ fprintf (fp, "%s\t%s\t%s\t%i\t%s\t%s\t%s\t%s",
+ escaped_str,
+ scheme_str,
+ url->host,
+ url->port,
+ url->path,
+ url->params ? url->params : "",
+ url->query ? url->query : "",
+ url->fragment ? url->fragment : "");
+
+ xfree (escaped_str);
+}
+
+/* This function writes out information on why a URL was rejected and its
+ context from download_child such as the URL being rejected and it's
+ parent's URL. The format it uses is comma separated values but with tabs. */
+static void
+write_reject_log_reason (FILE *fp, reject_reason reason,
+ const struct url *url, const struct url *parent)
+{
+ const char *reason_str;
+
+ if (!fp)
+ return;
+
+ switch (reason)
+ {
+ case WG_RR_SUCCESS: reason_str = "SUCCESS"; break;
+ case WG_RR_BLACKLIST: reason_str = "BLACKLIST"; break;
+ case WG_RR_NOTHTTPS: reason_str = "NOTHTTPS"; break;
+ case WG_RR_NONHTTP: reason_str = "NONHTTP"; break;
+ case WG_RR_ABSOLUTE: reason_str = "ABSOLUTE"; break;
+ case WG_RR_DOMAIN: reason_str = "DOMAIN"; break;
+ case WG_RR_PARENT: reason_str = "PARENT"; break;
+ case WG_RR_LIST: reason_str = "LIST"; break;
+ case WG_RR_REGEX: reason_str = "REGEX"; break;
+ case WG_RR_RULES: reason_str = "RULES"; break;
+ case WG_RR_SPANNEDHOST: reason_str = "SPANNEDHOST"; break;
+ case WG_RR_ROBOTS: reason_str = "ROBOTS"; break;
+ default: reason_str = "UNKNOWN"; break;
+ }
+
+ fprintf (fp, "%s\t", reason_str);
+ write_reject_log_url (fp, url);
+ fprintf (fp, "\t");
+ write_reject_log_url (fp, parent);
+ fprintf (fp, "\n");
+}
+
+/* vim:set sts=2 sw=2 cino+={s: */