From: Martti Rannanjärvi <martti.rannanjarvi@dovecot.fi>
Date: Sun, 4 Dec 2016 10:47:22 +0000 (+0200)
Subject: lib: Add error_r to t_readlink and its callers
X-Git-Tag: 2.3.0.rc1~2215
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=dd645357a6b851a3a9527d16e2bced731e46dcaa;p=thirdparty%2Fdovecot%2Fcore.git

lib: Add error_r to t_readlink and its callers
---

diff --git a/src/config/doveconf.c b/src/config/doveconf.c
index 0cc72e4239..439faccb03 100644
--- a/src/config/doveconf.c
+++ b/src/config/doveconf.c
@@ -684,12 +684,14 @@ static void hostname_verify_format(const char *arg)
 
 static void check_wrong_config(const char *config_path)
 {
-	const char *base_dir, *symlink_path, *prev_path;
+	const char *base_dir, *symlink_path, *prev_path, *error;
 
 	base_dir = get_setting("master", "base_dir");
 	symlink_path = t_strconcat(base_dir, "/"PACKAGE".conf", NULL);
-	if (t_readlink(symlink_path, &prev_path) < 0)
+	if (t_readlink(symlink_path, &prev_path, &error) < 0) {
+		i_error("t_readlink(%s) failed: %s", symlink_path, error);
 		return;
+	}
 
 	if (strcmp(prev_path, config_path) != 0) {
 		i_warning("Dovecot was last started using %s, "
diff --git a/src/lib-master/master-instance.c b/src/lib-master/master-instance.c
index 5baf04f543..92073d45f6 100644
--- a/src/lib-master/master-instance.c
+++ b/src/lib-master/master-instance.c
@@ -58,15 +58,17 @@ static void
 master_instance_update_config_path(struct master_instance_list *list,
 				   struct master_instance *inst)
 {
-	const char *path, *config_path;
+	const char *path, *config_path, *error;
 
 	/* update instance's config path if it has changed */
 	path = t_strconcat(inst->base_dir, "/"PACKAGE".conf", NULL);
-	if (t_readlink(path, &config_path) == 0) {
-		if (null_strcmp(inst->config_path, config_path) != 0) {
-			inst->config_path = p_strdup(list->pool, config_path);
-			list->config_paths_changed = TRUE;
-		}
+	if (t_readlink(path, &config_path, &error) < 0) {
+		i_error("t_readlink(%s) failed: %s", path, error);
+		return;
+	}
+	if (null_strcmp(inst->config_path, config_path) != 0) {
+		inst->config_path = p_strdup(list->pool, config_path);
+		list->config_paths_changed = TRUE;
 	}
 }
 
diff --git a/src/lib-master/master-service.c b/src/lib-master/master-service.c
index 6e53db7d01..78eb2da2a5 100644
--- a/src/lib-master/master-service.c
+++ b/src/lib-master/master-service.c
@@ -424,8 +424,9 @@ static bool get_instance_config(const char *name, const char **config_path_r)
 	inst = master_instance_list_find_by_name(list, name);
 	if (inst != NULL) {
 		path = t_strdup_printf("%s/dovecot.conf", inst->base_dir);
-		if (t_readlink(path, config_path_r) < 0)
-			i_fatal("readlink(%s) failed: %m", path);
+		const char *error;
+		if (t_readlink(path, config_path_r, &error) < 0)
+			i_fatal("t_readlink(%s) failed: %s", path, error);
 	}
 	master_instance_list_deinit(&list);
 	return inst != NULL;
diff --git a/src/lib-storage/index/dbox-common/dbox-storage.c b/src/lib-storage/index/dbox-common/dbox-storage.c
index 3a8ad5265a..0045cebbaf 100644
--- a/src/lib-storage/index/dbox-common/dbox-storage.c
+++ b/src/lib-storage/index/dbox-common/dbox-storage.c
@@ -32,12 +32,12 @@ static bool
 dbox_alt_path_has_changed(const char *root_dir, const char *alt_path,
 			  const char *alt_path2, const char *alt_symlink_path)
 {
-	const char *linkpath;
+	const char *linkpath, *error;
 
-	if (t_readlink(alt_symlink_path, &linkpath) < 0) {
+	if (t_readlink(alt_symlink_path, &linkpath, &error) < 0) {
 		if (errno == ENOENT)
 			return alt_path != NULL;
-		i_error("readlink(%s) failed: %m", alt_symlink_path);
+		i_error("t_readlink(%s) failed: %s", alt_symlink_path, error);
 		return FALSE;
 	}
 
diff --git a/src/lib-storage/mailbox-list.c b/src/lib-storage/mailbox-list.c
index 9761e6bcac..f4011b6dc7 100644
--- a/src/lib-storage/mailbox-list.c
+++ b/src/lib-storage/mailbox-list.c
@@ -1691,7 +1691,7 @@ int mailbox_list_dirent_is_alias_symlink(struct mailbox_list *list,
 		return 1;
 
 	T_BEGIN {
-		const char *path, *linkpath;
+		const char *path, *linkpath, *error;
 
 		path = t_strconcat(dir_path, "/", d->d_name, NULL);
 		if (lstat(path, &st) < 0) {
@@ -1700,8 +1700,8 @@ int mailbox_list_dirent_is_alias_symlink(struct mailbox_list *list,
 			ret = -1;
 		} else if (!S_ISLNK(st.st_mode)) {
 			ret = 0;
-		} else if (t_readlink(path, &linkpath) < 0) {
-			i_error("readlink(%s) failed: %m", path);
+		} else if (t_readlink(path, &linkpath, &error) < 0) {
+			i_error("t_readlink(%s) failed: %s", path, error);
 			ret = -1;
 		} else {
 			/* it's an alias only if it points to the same
diff --git a/src/lib/path-util.c b/src/lib/path-util.c
index b9e5f7c361..b2eba3b5a0 100644
--- a/src/lib/path-util.c
+++ b/src/lib/path-util.c
@@ -48,8 +48,10 @@ int t_get_current_dir(const char **dir_r)
 	return 0;
 }
 
-int t_readlink(const char *path, const char **dest_r)
+int t_readlink(const char *path, const char **dest_r, const char **error_r)
 {
+	i_assert(error_r != NULL);
+
 	/* @UNSAFE */
 	ssize_t ret;
 	char *dest;
@@ -60,8 +62,10 @@ int t_readlink(const char *path, const char **dest_r)
 		size = nearest_power(size+1);
 		dest = t_buffer_get(size);
 	}
-	if (ret < 0)
+	if (ret < 0) {
+		*error_r = t_strdup_printf("readlink() failed: %m");
 		return -1;
+	}
 
 	dest[ret] = '\0';
 	t_buffer_alloc(ret + 1);
diff --git a/src/lib/path-util.h b/src/lib/path-util.h
index fc7b72a7b2..af30e23e00 100644
--- a/src/lib/path-util.h
+++ b/src/lib/path-util.h
@@ -2,15 +2,22 @@
 #define PATH_UTIL_H
 
 /* Returns path as absolute path. If it's not already absolute path,
-   it's assumed to be relative to current working directory. */
+ * it's assumed to be relative to current working directory.
+ *
+ * In the t_abspath functions, the returned paths are not normalized. This
+ * means that './' and '../' are not resolved, but they left in the returned
+ * path as given in the parameters. Symbolic links are not resolved either.
+ */
 const char *t_abspath(const char *path);
 /* Like t_abspath(), but path is relative to given root. */
 const char *t_abspath_to(const char *path, const char *root);
 
 /* Returns current directory, allocated from data stack. */
 int t_get_current_dir(const char **dir_r);
-/* Returns symlink destination, allocated from data stack. */
-int t_readlink(const char *path, const char **dest_r);
+
+/* Get symlink destination allocated from data stack. Returns 0 on success and
+ * -1 on failure. error_r is set on failure and cannot be NULL. */
+int t_readlink(const char *path, const char **dest_r, const char **error_r);
 
 /* Update binpath to be absolute:
    a) begins with '/' -> no change