Fix for FS 6404 and functionalize some cachedir handling stuff

In order to best resolve bug 6404, move some cachedir handling stuff out of
sync.c and into util.c and create two new functions: filecache_find and
filecache_setup. sync.c was rewritten to use these, and alpm_fetch_pkgurl
now also uses these routines.

Signed-off-by: Dan McGee <dan@archlinux.org>

1 files changed, 68 insertions, 1 deletions

diff --git a/lib/libalpm/util.c b/lib/libalpm/util.c
index 64371348..72bc9673 100644
--- a/lib/libalpm/util.c
+++ b/lib/libalpm/util.c
@@ -48,6 +48,7 @@
 #include "error.h"
 #include "package.h"
 #include "alpm.h"
+#include "alpm_list.h"
 #include "md5.h"
 
 #ifndef HAVE_STRVERSCMP
@@ -301,7 +302,7 @@ static void _strnadd(char **str, const char *append, unsigned int count)
 	if(*str) {
 		*str = realloc(*str, strlen(*str) + count + 1);
 	} else {
-		*str = calloc(sizeof(char), count + 1);
+		*str = calloc(count + 1, sizeof(char));
 	}
 
 	strncat(*str, append, count);
@@ -542,6 +543,72 @@ int _alpm_str_cmp(const void *s1, const void *s2)
 	return(strcmp(s1, s2));
 }
 
+/** Find a package file in an alpm cachedir.
+ * @param filename name of package file to find
+ * @return malloced path of file, NULL if not found
+ */
+char *_alpm_filecache_find(const char* filename)
+{
+	struct stat buf;
+	char path[PATH_MAX];
+	char *retpath;
+	alpm_list_t *i;
+
+	/* Loop through the cache dirs until we find a matching file */
+	for(i = alpm_option_get_cachedirs(); i; i = alpm_list_next(i)) {
+		snprintf(path, PATH_MAX, "%s%s", (char*)alpm_list_getdata(i),
+				filename);
+		if(stat(path, &buf) == 0) {
+			/* TODO maybe check to make sure it is readable? */
+			retpath = strdup(path);
+			_alpm_log(PM_LOG_DEBUG, "found cached pkg: %s", retpath);
+			return(retpath);
+		}
+	}
+	/* package wasn't found in any cachedir */
+	return(NULL);
+}
+
+/** Check the alpm cachedirs for existance and find a writable one.
+ * If no valid cache directory can be found, use /tmp.
+ * @return pointer to a writable cache directory.
+ */
+const char *_alpm_filecache_setup(void)
+{
+	struct stat buf;
+	alpm_list_t *i, *tmp;
+	char *cachedir;
+
+	/* Loop through the cache dirs until we find a writeable dir */
+	for(i = alpm_option_get_cachedirs(); i; i = alpm_list_next(i)) {
+		cachedir = alpm_list_getdata(i);
+		if(stat(cachedir, &buf) != 0) {
+			/* cache directory does not exist.... try creating it */
+			_alpm_log(PM_LOG_WARNING, _("no %s cache exists, creating...\n"),
+					cachedir);
+			alpm_logaction("warning: no %s cache exists, creating...",
+					cachedir);
+			if(_alpm_makepath(cachedir) == 0) {
+				_alpm_log(PM_LOG_DEBUG, "using cachedir: %s", cachedir);
+				return(cachedir);
+			}
+		} else if(S_ISDIR(buf.st_mode) && (buf.st_mode & S_IWUSR)) {
+			_alpm_log(PM_LOG_DEBUG, "using cachedir: %s", cachedir);
+			return(cachedir);
+		}
+	}
+
+	/* we didn't find a valid cache directory. use /tmp. */
+	i = alpm_option_get_cachedirs();
+	tmp = alpm_list_add(NULL, strdup("/tmp/"));
+	FREELIST(i);
+	alpm_option_set_cachedirs(tmp);
+	_alpm_log(PM_LOG_DEBUG, "using cachedir: %s", "/tmp/");
+	_alpm_log(PM_LOG_WARNING, _("couldn't create package cache, using /tmp instead"));
+	alpm_logaction("warning: couldn't create package cache, using /tmp instead");
+	return(alpm_list_getdata(tmp));
+}
+
 /** Get the md5 sum of file.
  * @param filename name of the file
  * @return the checksum on success, NULL on error