replaced fseek with fseeko, this should enable large file support

src/cache.c

@@ -234,7 +234,7 @@ static int Meta_read(Cache *cf)
     }
 
     fread(&(cf->time), sizeof(long), 1, fp);
-    fread(&(cf->content_length), sizeof(long), 1, fp);
+    fread(&(cf->content_length), sizeof(off_t), 1, fp);
     fread(&(cf->blksz), sizeof(int), 1, fp);
     fread(&(cf->segbc), sizeof(long), 1, fp);
 
@@ -282,7 +282,7 @@ static int Meta_write(const Cache *cf)
     }
 
     fwrite(&(cf->time), sizeof(long), 1, fp);
-    fwrite(&(cf->content_length), sizeof(long), 1, fp);
+    fwrite(&(cf->content_length), sizeof(off_t), 1, fp);
     fwrite(&(cf->blksz), sizeof(int), 1, fp);
     fwrite(&(cf->segbc), sizeof(long), 1, fp);
     fwrite(cf->seg, sizeof(Seg), cf->segbc, fp);
@@ -355,9 +355,9 @@ static long Data_read(const Cache *cf, long offset, long len,
         return -1;
     }
 
-    if (fseek(fp, offset, SEEK_SET)) {
-        /* fseek failed */
-        fprintf(stderr, "Data_read(): fseek(): %s\n", strerror(errno));
+    if (fseeko(fp, offset, SEEK_SET)) {
+        /* fseeko failed */
+        fprintf(stderr, "Data_read(): fseeko(): %s\n", strerror(errno));
         goto cleanup;
     }
 
@@ -405,9 +405,9 @@ static long Data_write(const Cache *cf, long offset, long len,
         return -1;
     }
 
-    if (fseek(fp, offset, SEEK_SET)) {
-        /* fseek failed */
-        fprintf(stderr, "Data_write(): fseek(): %s\n", strerror(errno));
+    if (fseeko(fp, offset, SEEK_SET)) {
+        /* fseeko failed */
+        fprintf(stderr, "Data_write(): fseeko(): %s\n", strerror(errno));
         goto cleanup;
     }
 
@@ -556,6 +556,7 @@ static void Cache_delete(const char *fn)
 
 Cache *Cache_open(const char *fn)
 {
+    int res = 0;
     /* Check if both metadata and data file exist */
     if (Cache_exist(fn)) {
         return NULL;

src/cache.h

@@ -8,19 +8,8 @@
  * \file cache.h
  * \brief cache related structures and functions
  * \details
- * Metadata:
  *   - We store the metadata and the actual data separately in two
- * different folders.
- *   - The metadata file should follow the following format:
- *      - file length (long)
- *      - CURLINFO_FILETIME
- *      - segment count (int)
- *      - individual segments (array of seg)
- * \note
- *   - We are using 'long' to store file size, because the offset in fseek() is
- * in long, because the way we use the cache system, you cannot seek past
- * long. So the biggest file size has to be able to be stored in long. This
- * makes this program architecturally dependent, i.e. i386 vs amd64
+ * separate folders.
  */
 
 /**
@@ -34,7 +23,7 @@ typedef uint8_t Seg;
 typedef struct {
     char *p_url; /**< the filename from the http server */
     long time; /**<the modified time of the file */
-    long content_length; /**<the size of the file */
+    off_t content_length; /**<the size of the file */
     int blksz; /**<the block size of the data file */
     long segbc; /**<segment array byte count */
     Seg *seg; /**< the detail of each segment */