Factor out "read_sha1_file" into mapping/inflating/unmapping.

diff --git a/read-cache.c b/read-cache.c
index c924a6e0fc4c36bad6f23cb87ee59518c771f936..4d750506e97af68013aa25e192c569da557701fd 100644 (file)
--- a/read-cache.c
+++ b/read-cache.c
@@ -1,3 +1,8 @@
+/*
+ * GIT - The information manager from hell
+ *
+ * Copyright (C) Linus Torvalds, 2005
+ */
 #include "cache.h"
 
 const char *sha1_file_directory = NULL;
@@ -79,33 +84,40 @@ char *sha1_file_name(unsigned char *sha1)
        return base;
 }
 
-void * read_sha1_file(unsigned char *sha1, char *type, unsigned long *size)
+void *map_sha1_file(unsigned char *sha1, unsigned long *size)
 {
-       z_stream stream;
-       char buffer[8192];
-       struct stat st;
-       int i, fd, ret, bytes;
-       void *map, *buf;
        char *filename = sha1_file_name(sha1);
+       int fd = open(filename, O_RDONLY);
+       struct stat st;
+       void *map;
 
-       fd = open(filename, O_RDONLY);
        if (fd < 0) {
                perror(filename);
                return NULL;
        }
        if (fstat(fd, &st) < 0) {
-               close(fd);
+               close(fd);  
                return NULL;
        }
        map = mmap(NULL, st.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
        close(fd);
        if (-1 == (int)(long)map)
                return NULL;
+       *size = st.st_size;
+       return map;
+}
+
+void * unpack_sha1_file(void *map, unsigned long mapsize, char *type, unsigned long *size)
+{
+       int ret, bytes;
+       z_stream stream;
+       char buffer[8192];
+       char *buf;
 
        /* Get the data stream */
        memset(&stream, 0, sizeof(stream));
        stream.next_in = map;
-       stream.avail_in = st.st_size;
+       stream.avail_in = mapsize;
        stream.next_out = buffer;
        stream.avail_out = sizeof(buffer);
 
@@ -113,6 +125,7 @@ void * read_sha1_file(unsigned char *sha1, char *type, unsigned long *size)
        ret = inflate(&stream, 0);
        if (sscanf(buffer, "%10s %lu", type, size) != 2)
                return NULL;
+
        bytes = strlen(buffer) + 1;
        buf = malloc(*size);
        if (!buf)
@@ -130,6 +143,20 @@ void * read_sha1_file(unsigned char *sha1, char *type, unsigned long *size)
        return buf;
 }
 
+void * read_sha1_file(unsigned char *sha1, char *type, unsigned long *size)
+{
+       unsigned long mapsize;
+       void *map, *buf;
+
+       map = map_sha1_file(sha1, &mapsize);
+       if (map) {
+               buf = unpack_sha1_file(map, mapsize, type, size);
+               munmap(map, mapsize);
+               return buf;
+       }
+       return NULL;
+}
+
 int write_sha1_file(char *buf, unsigned len)
 {
        int size;
@@ -168,7 +195,7 @@ int write_sha1_file(char *buf, unsigned len)
 int write_sha1_buffer(unsigned char *sha1, void *buf, unsigned int size)
 {
        char *filename = sha1_file_name(sha1);
-       int i, fd;
+       int fd;
 
        fd = open(filename, O_WRONLY | O_CREAT | O_EXCL, 0666);
        if (fd < 0)
@@ -223,6 +250,7 @@ int read_cache(void)
        if (fd < 0)
                return (errno == ENOENT) ? 0 : error("open failed");
 
+       size = 0; // avoid gcc warning
        map = (void *)-1;
        if (!fstat(fd, &st)) {
                map = NULL;