pacman: add cache server support

Signed-off-by: Andrew Gregory <andrew.gregory.8@gmail.com>

doc/pacman.conf.5.asciidoc

@@ -240,6 +240,12 @@ number.
 	general configuration options. Wildcards in the specified paths will get
 	expanded based on linkman:glob[7] rules.
 
+*CacheServer =* url::
+	A full URL to a location where the packages, and signatures (if
+	available) for this repository can be found.  Cache servers will be tried
+	before any non-cache servers, will not be removed from the server pool for
+	404 download errors, and will not be used for database files.
+
 *Server =* url::
 	A full URL to a location where the database, packages, and signatures (if
 	available) for this repository can be found.

src/pacman/conf.c

@@ -172,6 +172,7 @@ void config_repo_free(config_repo_t *repo)
 		return;
 	}
 	free(repo->name);
+	FREELIST(repo->cache_servers);
 	FREELIST(repo->servers);
 	free(repo);
 }
@@ -781,6 +782,21 @@ static char *replace_server_vars(config_t *c, config_repo_t *r, const char *s)
 	}
 }
 
+static int replace_server_list_vars(config_t *c, config_repo_t *r, alpm_list_t *list)
+{
+	alpm_list_t *i;
+	for(i = list; i; i = i->next) {
+		char *newurl = replace_server_vars(c, r, i->data);
+		if(newurl == NULL) {
+			return -1;
+		} else {
+			free(i->data);
+			i->data = newurl;
+		}
+	}
+	return 0;
+}
+
 static int register_repo(config_repo_t *repo)
 {
 	alpm_list_t *i;
@@ -797,6 +813,15 @@ static int register_repo(config_repo_t *repo)
 			repo->usage, repo->name);
 	alpm_db_set_usage(db, repo->usage);
 
+	for(i = repo->cache_servers; i; i = alpm_list_next(i)) {
+		const char *value = i->data;
+		if(alpm_db_add_cache_server(db, value) != 0) {
+			/* pm_errno is set by alpm_db_setserver */
+			pm_printf(ALPM_LOG_ERROR, _("could not add cache server URL to database '%s': %s (%s)\n"),
+					alpm_db_get_name(db), value, alpm_strerror(alpm_errno(config->handle)));
+			return 1;
+		}
+	}
 	for(i = repo->servers; i; i = alpm_list_next(i)) {
 		const char *value = i->data;
 		if(alpm_db_add_server(db, value) != 0) {
@@ -982,7 +1007,10 @@ static int _parse_repo(const char *key, char *value, const char *file,
 	} \
 } while(0)
 
-	if(strcmp(key, "Server") == 0) {
+	if(strcmp(key, "CacheServer") == 0) {
+		CHECK_VALUE(value);
+		repo->cache_servers = alpm_list_add(repo->cache_servers, strdup(value));
+	} else if(strcmp(key, "Server") == 0) {
 		CHECK_VALUE(value);
 		repo->servers = alpm_list_add(repo->servers, strdup(value));
 	} else if(strcmp(key, "SigLevel") == 0) {
@@ -1162,17 +1190,11 @@ int setdefaults(config_t *c)
 
 	for(i = c->repos; i; i = i->next) {
 		config_repo_t *r = i->data;
-		alpm_list_t *j;
 		SETDEFAULT(r->usage, ALPM_DB_USAGE_ALL);
 		r->siglevel = merge_siglevel(c->siglevel, r->siglevel, r->siglevel_mask);
-		for(j = r->servers; j; j = j->next) {
-			char *newurl = replace_server_vars(c, r, j->data);
-			if(newurl == NULL) {
-				return -1;
-			} else {
-				free(j->data);
-				j->data = newurl;
-			}
+		if(replace_server_list_vars(c, r, r->cache_servers) == -1
+				|| replace_server_list_vars(c, r, r->servers) == -1) {
+			return -1;
 		}
 	}
 

src/pacman/conf.h

@@ -37,6 +37,7 @@ typedef struct __colstr_t {
 
 typedef struct __config_repo_t {
 	char *name;
+	alpm_list_t *cache_servers;
 	alpm_list_t *servers;
 	int usage;
 	int siglevel;

src/pacman/pacman-conf.c

@@ -236,6 +236,7 @@ static void dump_repo(config_repo_t *repo)
 {
 	show_usage("Usage", repo->usage);
 	show_siglevel("SigLevel", repo->siglevel, 0);
+	show_list_str("CacheServer", repo->cache_servers);
 	show_list_str("Server", repo->servers);
 }
 
@@ -310,6 +311,8 @@ static int list_repo_directives(void)
 	for(i = directives; i; i = i->next) {
 		if(strcasecmp(i->data, "Server") == 0) {
 			show_list_str("Server", repo->servers);
+		} else if(strcasecmp(i->data, "CacheServer") == 0) {
+			show_list_str("CacheServer", repo->cache_servers);
 		} else if(strcasecmp(i->data, "SigLevel") == 0) {
 			show_siglevel("SigLevel", repo->siglevel, 0);
 		} else if(strcasecmp(i->data, "Usage") == 0) {

test/pacman/meson.build

@@ -1,5 +1,6 @@
 pacman_tests = [
   'tests/backup001.py',
+  'tests/cache-server-basic.py',
   'tests/clean001.py',
   'tests/clean002.py',
   'tests/clean003.py',

test/pacman/tests/cache-server-basic.py

@@ -0,0 +1,37 @@
+self.description = "basic cache server test"
+self.require_capability("curl")
+
+pkgs = [ self.addpkg2db('sync', pmpkg("pkg{}".format(i))) for i in range(0, 5) ]
+
+# TODO: hack to prevent pacman trying to validate the downloaded packages
+p404 = pmpkg('pkg404')
+self.addpkg2db('sync', p404)
+
+cache_url = self.add_simple_http_server({
+    '/{}'.format(pkgs[0].filename()): { 'body': 'CacheServer' },
+    # 404 for packages 1-3
+    '/{}'.format(pkgs[4].filename()): { 'body': 'CacheServer' },
+})
+normal_url = self.add_simple_http_server({
+    '/{}'.format(pkgs[0].filename()): { 'body': 'Server' },
+    '/{}'.format(pkgs[1].filename()): { 'body': 'Server' },
+    '/{}'.format(pkgs[2].filename()): { 'body': 'Server' },
+    '/{}'.format(pkgs[3].filename()): { 'body': 'Server' },
+    '/{}'.format(pkgs[4].filename()): { 'body': 'Server' },
+})
+
+self.db['sync'].option['CacheServer'] = [ cache_url ]
+self.db['sync'].option['Server'] = [ normal_url ]
+self.db['sync'].syncdir = False
+self.cachepkgs = False
+
+self.args = '-S pkg0 pkg1 pkg2 pkg3 pkg4 pkg404'
+
+#self.addrule("PACMAN_RETCODE=0") # TODO
+self.addrule("PACMAN_OUTPUT={}".format(normal_url.replace("http://", "")))
+self.addrule("!PACMAN_OUTPUT={}".format(cache_url.replace("http://", "")))
+self.addrule("CACHE_FCONTENTS={}|CacheServer".format(pkgs[0].filename()))
+self.addrule("CACHE_FCONTENTS={}|Server".format(pkgs[1].filename()))
+self.addrule("CACHE_FCONTENTS={}|Server".format(pkgs[2].filename()))
+self.addrule("CACHE_FCONTENTS={}|Server".format(pkgs[3].filename()))
+self.addrule("CACHE_FCONTENTS={}|CacheServer".format(pkgs[4].filename()))