Added ftruncate().

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@2827 a1c6a512-1295-4272-9138-f99709370657

3 files changed, 33 insertions, 4 deletions

diff --git a/firmware/common/file.c b/firmware/common/file.c
index b869380..cf8c46c 100644
--- a/firmware/common/file.c
+++ b/firmware/common/file.c
@@ -90,7 +90,7 @@ int open(const char* pathname, int flags)
         case O_WRONLY:
             openfiles[fd].write = true;
             break;
-            
+
         default:
             DEBUGF("Only O_RDONLY and O_WRONLY is supported\n");
             errno = EROFS;
@@ -214,6 +214,31 @@ int remove(const char* name)
     return rc;
 }
 
+int ftruncate(int fd, unsigned int size)
+{
+    int rc, sector;
+
+    sector = size / SECTOR_SIZE;
+    if (size % SECTOR_SIZE)
+        sector++;
+
+    rc = fat_seek(&(openfiles[fd].fatfile), sector);
+    if (rc < 0) {
+        errno = EIO;
+        return -1;
+    }
+
+    rc = fat_truncate(&(openfiles[fd].fatfile));
+    if (rc < 0) {
+        errno = EIO;
+        return -2;
+    }
+
+    openfiles[fd].size = size;
+
+    return 0;
+}
+
 static int readwrite(int fd, void* buf, int count, bool write)
 {
     int sectors;
diff --git a/firmware/common/file.h b/firmware/common/file.h
index 7a7c63d..59ff717 100644
--- a/firmware/common/file.h
+++ b/firmware/common/file.h
@@ -56,6 +56,7 @@ extern int creat(const char *pathname, int mode);
 extern int write(int fd, void* buf, int count);
 extern int remove(const char* pathname);
 extern int rename(const char* oldname, const char* newname);
+extern int ftruncate(int fd, unsigned int size);
 
 #else
 #ifdef WIN32
diff --git a/firmware/drivers/fat.c b/firmware/drivers/fat.c
index 74bdbd3..ad1a7a0 100644
--- a/firmware/drivers/fat.c
+++ b/firmware/drivers/fat.c
@@ -1002,12 +1002,15 @@ int fat_truncate(struct fat_file *file)
 {
     /* truncate trailing clusters */
     int next;
-    int last = get_next_cluster(file->lastcluster);
-    while ( last && last != FAT_EOF_MARK ) {
+    int last = file->lastcluster;
+
+    LDEBUGF("fat_truncate(%x, %x)\n", file->firstcluster, last);
+
+    for ( last = get_next_cluster(last); last; last = next ) {
         next = get_next_cluster(last);
         update_fat_entry(last,0);
-        last = next;
     }
+    update_fat_entry(file->lastcluster,FAT_EOF_MARK);
 
     return 0;
 }