don't allocate char[PATH_MAX] for each file

This commit makes struct path allocation use strndup().
It reduices the memory footprint for struct path per file (issue #8).

3 files changed, 34 insertions, 27 deletions

diff --git a/src/mscp.c b/src/mscp.c
index 522a4c3..9989d54 100644
--- a/src/mscp.c
+++ b/src/mscp.c
@@ -714,7 +714,7 @@ out:
 
 /* cleanup-related functions */
 
-static void free_src(struct list_head *list)
+static void list_free_src(struct list_head *list)
 {
 	struct src *s;
 	s = list_entry(list, typeof(*s), list);
@@ -722,21 +722,14 @@ static void free_src(struct list_head *list)
 	free(s);
 }
 
-static void free_path(struct list_head *list)
+static void list_free_path(struct list_head *list)
 {
 	struct path *p;
 	p = list_entry(list, typeof(*p), list);
-	free(p);
+	free_path(p);
 }
 
-static void free_chunk(struct list_head *list)
-{
-	struct chunk *c;
-	c = list_entry(list, typeof(*c), list);
-	free(c);
-}
-
-static void free_thread(struct list_head *list)
+static void list_free_thread(struct list_head *list)
 {
 	struct mscp_thread *t;
 	t = list_entry(list, typeof(*t), list);
@@ -750,17 +743,17 @@ void mscp_cleanup(struct mscp *m)
 		m->first = NULL;
 	}
 
-	list_free_f(&m->src_list, free_src);
+	list_free_f(&m->src_list, list_free_src);
 	INIT_LIST_HEAD(&m->src_list);
 
-	list_free_f(&m->path_list, free_path);
+	list_free_f(&m->path_list, list_free_path);
 	INIT_LIST_HEAD(&m->path_list);
 
 	chunk_pool_release(&m->cp);
 	chunk_pool_init(&m->cp);
 
 	RWLOCK_WRITE_ACQUIRE(&m->thread_rwlock);
-	list_free_f(&m->thread_list, free_thread);
+	list_free_f(&m->thread_list, list_free_thread);
 	RWLOCK_RELEASE();
 }
 
diff --git a/src/path.c b/src/path.c
index e7837ac..5c70795 100644
--- a/src/path.c
+++ b/src/path.c
@@ -92,10 +92,9 @@ void chunk_pool_release(struct chunk_pool *cp)
 }
 
 /* paths of copy source resoltion */
-static int resolve_dst_path(const char *src_file_path, char *dst_file_path,
-			    struct path_resolve_args *a)
+static char *resolve_dst_path(const char *src_file_path, struct path_resolve_args *a)
 {
-        char copy[PATH_MAX + 1];
+        char copy[PATH_MAX + 1], dst_file_path[PATH_MAX + 1];
         char *prefix;
         int offset;
 	int ret;
@@ -104,7 +103,7 @@ static int resolve_dst_path(const char *src_file_path, char *dst_file_path,
         prefix = dirname(copy);
         if (!prefix) {
                 mscp_set_error("dirname: %s", strerrno());
-                return -1;
+                return NULL;
         }
 
 	offset = strlen(prefix) + 1;
@@ -147,12 +146,12 @@ static int resolve_dst_path(const char *src_file_path, char *dst_file_path,
 
 	if (ret >= PATH_MAX) {
 		mpr_warn(a->msg_fp, "Too long path: %s\n", dst_file_path);
-		return -1;
+		return NULL;
 	}
 
         mpr_debug(a->msg_fp, "file: %s -> %s\n", src_file_path, dst_file_path);
 
-        return 0;
+        return strndup(dst_file_path, PATH_MAX);
 }
 
 /* chunk preparation */
@@ -208,6 +207,15 @@ static int resolve_chunk(struct path *p, struct path_resolve_args *a)
         return 0;
 }
 
+void free_path(struct path *p)
+{
+	if (p->path)
+		free(p->path);
+	if (p->dst_path)
+		free(p->dst_path);
+	free(p);
+}
+
 static int append_path(sftp_session sftp, const char *path, struct stat st,
 		       struct list_head *path_list, struct path_resolve_args *a)
 {
@@ -220,13 +228,16 @@ static int append_path(sftp_session sftp, const char *path, struct stat st,
 
 	memset(p, 0, sizeof(*p));
 	INIT_LIST_HEAD(&p->list);
-	strncpy(p->path, path, PATH_MAX - 1);
+	p->path = strndup(path, PATH_MAX);
+	if (!p->path)
+		goto free_out;
 	p->size = st.st_size;
 	p->mode = st.st_mode;
 	p->state = FILE_STATE_INIT;
 	lock_init(&p->lock);
 
-	if (resolve_dst_path(p->path, p->dst_path, a) < 0)
+	p->dst_path = resolve_dst_path(p->path, a);
+	if (!p->dst_path)
 		goto free_out;
 
 	if (resolve_chunk(p, a) < 0)
@@ -239,7 +250,7 @@ static int append_path(sftp_session sftp, const char *path, struct stat st,
 	return 0;
 
 free_out:
-	free(p);
+	free_path(p);
 	return -1;
 }
 
diff --git a/src/path.h b/src/path.h
index dbaa585..ffef60b 100644
--- a/src/path.h
+++ b/src/path.h
@@ -14,11 +14,11 @@
 struct path {
 	struct list_head	list;	/* mscp->path_list */
 
-	char	path[PATH_MAX];		/* file path */
-	size_t	size;			/* size of file on this path */
-	mode_t	mode;			/* permission */
+	char	*path;		/* file path */
+	size_t	size;		/* size of file on this path */
+	mode_t	mode;		/* permission */
 
-	char	dst_path[PATH_MAX];	/* copy dst path */
+	char	*dst_path;	/* copy dst path */
 
 	int	state;
 	lock	lock;
@@ -93,6 +93,9 @@ struct path_resolve_args {
 int walk_src_path(sftp_session src_sftp, const char *src_path,
 		  struct list_head *path_list, struct path_resolve_args *a);
 
+/* free struct path */
+void free_path(struct path *p);
+
 /* copy a chunk. either src_sftp or dst_sftp is not null, and another is null */
 int copy_chunk(FILE *msg_fp, struct chunk *c,
 	       sftp_session src_sftp, sftp_session dst_sftp,