Adding upstream version 2.12.0.upstream/2.12.0

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 452 insertions, 0 deletions

diff --git a/src/ult_src.c b/src/ult_src.c
new file mode 100644
index 0000000..c21aa51
--- /dev/null
+++ b/src/ult_src.c
@@ -0,0 +1,452 @@
+/*
+ * ult_src.c: Find the ultimate source of a page
+ *
+ * Copyright (C) 1994, 1995 Graeme W. Wilford. (Wilf.)
+ * Copyright (C) 2001, 2002, 2003, 2004, 2006, 2007, 2008, 2009, 2010, 2011,
+ *               2012 Colin Watson.
+ *
+ * This file is part of man-db.
+ *
+ * man-db 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 2 of the License, or
+ * (at your option) any later version.
+ *
+ * man-db 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 man-db; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ *
+ * code to seek out the original (ultimate) source man file for
+ * any specified man file. Soft and hard links and .so inclusions
+ * are traced. Use: reduce amount of cat files to a minimum.
+ *
+ * Mon May  2 11:14:28 BST 1994 Wilf. (G.Wilford@ee.surrey.ac.uk)
+ */
+
+#ifdef HAVE_CONFIG_H
+#  include "config.h"
+#endif /* HAVE_CONFIG_H */
+
+#include <string.h>
+#include <stdbool.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <ctype.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <errno.h>
+#include <assert.h>
+#include <dirent.h>
+#include <unistd.h>
+
+#include "canonicalize.h"
+#include "dirname.h"
+#include "error.h"
+#include "gl_array_list.h"
+#include "gl_hash_map.h"
+#include "gl_xlist.h"
+#include "gl_xmap.h"
+#include "xalloc.h"
+#include "xstrndup.h"
+#include "xvasprintf.h"
+
+#include "gettext.h"
+#define _(String) gettext (String)
+
+#include "manconfig.h"
+
+#include "compression.h"
+#include "debug.h"
+#include "glcontainers.h"
+
+#include "decompress.h"
+#include "ult_src.h"
+
+void gripe_canonicalize_failed (const char *path)
+{
+	if (quiet < 2) {
+		if (errno == ENOENT)
+			error (0, 0, _("warning: %s is a dangling symlink"),
+			       path);
+		else
+			error (0, errno, _("can't resolve %s"), path);
+	}
+}
+
+/* Find minimum value hard link filename for given file and inode.
+ * Returns a newly allocated string.
+ */
+static char *ult_hardlink (const char *fullpath, ino_t inode)
+{
+	DIR *mdir;
+	struct dirent *manlist;
+	char *base, *dir, *ret;
+	const char *slash;
+
+	slash = strrchr (fullpath, '/');
+	assert (slash);
+	dir = xstrndup (fullpath, slash - fullpath);
+	base = xstrdup (++slash);
+
+	mdir = opendir (dir);
+	if (mdir == NULL) {
+		if (quiet < 2)
+			error (0, errno, _("can't search directory %s"), dir);
+		free (dir);
+		free (base);
+		return NULL;
+	}
+
+	while ((manlist = readdir (mdir))) {
+		if (manlist->d_ino == inode &&
+		    strcmp (base, manlist->d_name) > 0) {
+			free (base);
+			base = xstrdup (manlist->d_name);
+			debug ("ult_hardlink: (%s)\n", base);
+		}
+	}
+	closedir (mdir);
+
+	/* If we already are the link with the smallest name value */
+	/* return NULL */
+
+	if (strcmp (base, slash) == 0) {
+		free (dir);
+		free (base);
+		return NULL;
+	}
+
+	ret = xasprintf ("%s/%s", dir, base);
+	free (dir);
+	free (base);
+	return ret;
+}
+
+/* Resolve all symbolic links within 'fullpath'.
+ * Returns a newly allocated string.
+ */
+static char *ult_softlink (const char *fullpath)
+{
+	char *resolved_path;
+
+	resolved_path = canonicalize_file_name (fullpath);
+	if (!resolved_path) {
+		/* discard the unresolved path */
+		gripe_canonicalize_failed (fullpath);
+		return NULL;
+	}
+
+	debug ("ult_softlink: (%s)\n", resolved_path);
+
+	return resolved_path;
+}
+
+static char *find_include_directive (char *path)
+{
+	decompress *decomp;
+	const char *buffer;
+	char *directive;
+
+	decomp = decompress_open (path, DECOMPRESS_ALLOW_INPROCESS);
+	if (!decomp) {
+		if (quiet < 2)
+			error (0, errno, _("can't open %s"), path);
+		return NULL;
+	}
+	decompress_start (decomp);
+
+	/* make sure that we skip over any comments */
+	do {
+		buffer = decompress_readline (decomp);
+	} while (buffer && STRNEQ (buffer, ".\\\"", 3));
+
+	directive = xstrdup (buffer ? buffer : "");
+
+	decompress_wait (decomp);
+	decompress_free (decomp);
+
+	return directive;
+}
+
+/* Test 'buffer' to see if it contains a .so include. If so and it's not an
+ * absolute filename, return newly allocated string whose contents are the
+ * include.
+ */
+static char *test_for_include (const char *buffer)
+{
+	if (!buffer)
+		return NULL;
+
+	/* strip out any leading whitespace (if any) */
+	while (CTYPE (isspace, *buffer))
+		buffer++;
+
+	/* see if the `command' is a .so */
+	if (strncmp (buffer, ".so", 3) == 0) {
+		buffer += 3;
+
+		/* strip out any whitespace between the command and
+		   its argument */
+		while (CTYPE (isspace, *buffer))
+			buffer++;
+
+		/* If .so's argument is an absolute filename, it could be
+		 * either (i) a macro inclusion, (ii) a non local manual page
+		 * or (iii) a (somewhat bogus) reference to a local manual
+		 * page.
+		 *
+		 * If (i) or (ii), we must not follow the reference. (iii) is
+		 * a problem with the manual page, thus we don't want to
+		 * follow any absolute inclusions in our quest for the
+		 * ultimate source file */
+		if (*buffer != '/') {
+			const char *end = buffer;
+			while (*end && !CTYPE (isspace, *end))
+				++end;
+			return xstrndup (buffer, end - buffer);
+		}
+	}
+	return NULL;
+}
+
+static char *find_include (const char *name, const char *path,
+			   const char *include)
+{
+	char *target;
+	struct compression *comp;
+
+	/* Restore the original path from before ult_softlink() etc., in
+	 * case it went outside the mantree.
+	 */
+	target = xasprintf ("%s/%s", path, include);
+	assert (target);
+
+	/* If the original path from above doesn't exist, try to create new
+	 * path as if the "include" was relative to the current man page.
+	 */
+	if (!CAN_ACCESS (target, F_OK)) {
+		comp = comp_file (target);
+		free (target);
+		if (comp) {
+			target = comp->stem;
+			comp->stem = NULL; /* steal memory */
+		} else
+			target = NULL;
+	}
+
+	if (!target) {
+		char *dirname = dir_name (name);
+		char *temp_file = xasprintf ("%s/%s", dirname, include);
+		assert (temp_file);
+		free (dirname);
+
+		if (CAN_ACCESS (temp_file, F_OK))
+			/* Just plain include. */
+			target = xstrdup (temp_file);
+		else {
+			comp = comp_file (temp_file);
+			if (comp) {
+				target = comp->stem;
+				comp->stem = NULL; /* steal memory */
+			}
+		}
+		free (temp_file);
+	}
+
+	if (target) {
+		char *canonicalized = canonicalize_file_name (target);
+		if (canonicalized)
+			return canonicalized;
+		else {
+			gripe_canonicalize_failed (target);
+			free (target);
+			return NULL;
+		}
+	} else {
+		if (quiet < 2)
+			error (0, 0, _("can't resolve %s"), include);
+		return NULL;
+	}
+}
+
+struct ult_key {
+	char *name;
+	int flags;
+};
+
+static struct ult_key *ult_key_new (const char *name, int flags)
+{
+	struct ult_key *ukey = XMALLOC (struct ult_key);
+	ukey->name = xstrdup (name);
+	ukey->flags = flags;
+	return ukey;
+}
+
+static bool ATTRIBUTE_PURE ult_key_equals (const void *key1, const void *key2)
+{
+	struct ult_key *ukey1 = (struct ult_key *) key1;
+	struct ult_key *ukey2 = (struct ult_key *) key2;
+	return ukey1->flags == ukey2->flags &&
+	       STREQ (ukey1->name, ukey2->name);
+}
+
+static size_t ATTRIBUTE_PURE ult_key_hash (const void *key)
+{
+	struct ult_key *ukey = (struct ult_key *) key;
+	return string_hash (ukey->name) ^ (size_t) ukey->flags;
+}
+
+static void ult_key_free (const void *key)
+{
+	struct ult_key *ukey = (struct ult_key *) key;
+	free (ukey->name);
+	free (ukey);
+}
+
+static struct ult_value *ult_value_new (void)
+{
+	struct ult_value *uvalue = XMALLOC (struct ult_value);
+	uvalue->path = NULL;
+	uvalue->trace = new_string_list (GL_ARRAY_LIST, true);
+	return uvalue;
+}
+
+static void ult_value_free (const void *value)
+{
+	struct ult_value *uvalue = (struct ult_value *) value;
+	if (uvalue) {
+		free (uvalue->path);
+		gl_list_free (uvalue->trace);
+		free (uvalue);
+	}
+}
+
+gl_map_t ult_cache = NULL;
+
+/*
+ * Find the ultimate source file by following any ".so filename" directives
+ * in the first line of the man pages.  Also (optionally) trace symlinks and
+ * hard links(!).
+ *
+ * name is full pathname, path is the MANPATH directory (/usr/man)
+ * flags is a combination of SO_LINK | SOFT_LINK | HARD_LINK
+ */
+const struct ult_value *ult_src (const char *name, const char *path,
+				 struct stat *buf, int flags)
+{
+	char *base = xstrdup (name);
+	struct ult_key *key;
+	const struct ult_value *existing;
+	struct ult_value *value;
+	struct stat new_buf;
+
+	if (!ult_cache)
+		ult_cache = gl_map_create_empty (GL_HASH_MAP,
+						 ult_key_equals, ult_key_hash,
+						 ult_key_free, ult_value_free);
+	key = ult_key_new (name, flags);
+	if (gl_map_search (ult_cache, key, (const void **) &existing)) {
+		ult_key_free (key);
+		return existing;
+	}
+	value = ult_value_new ();
+
+	debug ("ult_src: File %s in mantree %s\n", name, path);
+
+	gl_list_add_last (value->trace, xstrdup (name));
+
+	/* as ult_softlink() & ult_hardlink() do all of their respective
+	 * resolving in one call, only need to sort them out once
+	 */
+
+	/* If we don't have a buf, allocate and assign one */
+	if (!buf && ((flags & SOFT_LINK) || (flags & HARD_LINK))) {
+		buf = &new_buf;
+		if (lstat (base, buf) == -1) {
+			if (quiet < 2)
+				error (0, errno, _("can't resolve %s"), base);
+			goto err;
+		}
+	}
+
+	/* Permit semi local (inter-tree) soft links */
+	if (flags & SOFT_LINK) {
+		assert (buf); /* initialised above */
+		if (S_ISLNK (buf->st_mode)) {
+			/* Is a symlink, resolve it. */
+			char *softlink = ult_softlink (base);
+			if (softlink) {
+				free (base);
+				base = softlink;
+			} else
+				goto err;
+		}
+	}
+
+	/* Only deal with local (inter-dir) HARD links */
+	if (flags & HARD_LINK) {
+		assert (buf); /* initialised above */
+		if (buf->st_nlink > 1) {
+			/* Has HARD links, find least value */
+			char *hardlink = ult_hardlink (base,
+						       buf->st_ino);
+			if (hardlink) {
+				free (base);
+				base = hardlink;
+			}
+		}
+	}
+
+	if (flags & SO_LINK) {
+		int i;
+		for (i = 0; i < 10; ++i) {
+			char *directive, *include;
+
+			directive = find_include_directive (base);
+			if (!directive)
+				goto err;
+
+			include = test_for_include (directive);
+			free (directive);
+			if (!include)
+				break;
+
+			free (base);
+			base = find_include (name, path, include);
+			free (include);
+			if (!base)
+				goto err;
+
+			debug ("ult_src: points to %s\n", base);
+
+			gl_list_add_last (value->trace, xstrdup (base));
+		}
+		if (i == 10) {
+			if (quiet < 2)
+				error (0, 0, _("%s is self referencing"),
+				       name);
+			goto err;
+		}
+	}
+
+	/* We have the ultimate source */
+	value->path = xstrdup (base);
+	gl_list_add_last (value->trace, xstrdup (base));
+	gl_map_put (ult_cache, key, value);
+	free (base);
+	return value;
+
+err:
+	/* The cache is short-lived and only within a single process, so
+	 * negative caching is fine.
+	 */
+	ult_value_free (value);
+	gl_map_put (ult_cache, key, NULL);
+	free (base);
+	return NULL;
+}