summaryrefslogtreecommitdiff
path: root/read-cache.c
diff options
context:
space:
mode:
authorJohannes Schindelin <Johannes.Schindelin@gmx.de>2006-07-08 18:42:41 +0200
committerJunio C Hamano <junkio@cox.net>2006-07-13 23:10:19 -0700
commit6d297f81373e19d86b8f02cb68120201d1b0ab1d (patch)
treef036ee3b98ce1a260895d8d3bec4889189dabafe /read-cache.c
parent4b7ce6e2d6ba088da50de1df38b040ea2c0b8f18 (diff)
downloadgit-6d297f81373e19d86b8f02cb68120201d1b0ab1d.tar.gz
Status update on merge-recursive in C
This is just an update for people being interested. Alex and me were busy with that project for a few days now. While it has progressed nicely, there are quite a couple TODOs in merge-recursive.c, just search for "TODO". For impatient people: yes, it passes all the tests, and yes, according to the evil test Alex did, it is faster than the Python script. But no, it is not yet finished. Biggest points are: - there are still three external calls - in the end, it should not be necessary to write the index more than once (just before exiting) - a lot of things can be refactored to make the code easier and shorter BTW we cannot just plug in git-merge-tree yet, because git-merge-tree does not handle renames at all. This patch is meant for testing, and as such, - it compile the program to git-merge-recur - it adjusts the scripts and tests to use git-merge-recur instead of git-merge-recursive - it provides "TEST", a script to execute the tests regarding -recursive - it inlines the changes to read-cache.c (read_cache_from(), discard_cache() and refresh_cache_entry()) Brought to you by Alex Riesen and Dscho Signed-off-by: Junio C Hamano <junkio@cox.net>
Diffstat (limited to 'read-cache.c')
-rw-r--r--read-cache.c104
1 files changed, 59 insertions, 45 deletions
diff --git a/read-cache.c b/read-cache.c
index a50d3612c8..9c0a9fc2a1 100644
--- a/read-cache.c
+++ b/read-cache.c
@@ -24,6 +24,11 @@ unsigned int active_nr = 0, active_alloc = 0, active_cache_changed = 0;
struct cache_tree *active_cache_tree = NULL;
+int cache_errno = 0;
+
+static void *cache_mmap = NULL;
+static size_t cache_mmap_size = 0;
+
/*
* This only updates the "non-critical" parts of the directory
* cache, ie the parts that aren't tracked by GIT, and only used
@@ -577,22 +582,6 @@ int add_cache_entry(struct cache_entry *ce, int option)
return 0;
}
-/* Three functions to allow overloaded pointer return; see linux/err.h */
-static inline void *ERR_PTR(long error)
-{
- return (void *) error;
-}
-
-static inline long PTR_ERR(const void *ptr)
-{
- return (long) ptr;
-}
-
-static inline long IS_ERR(const void *ptr)
-{
- return (unsigned long)ptr > (unsigned long)-1000L;
-}
-
/*
* "refresh" does not calculate a new sha1 file or bring the
* cache up-to-date for mode/content changes. But what it
@@ -604,14 +593,16 @@ static inline long IS_ERR(const void *ptr)
* For example, you'd want to do this after doing a "git-read-tree",
* to link up the stat cache details with the proper files.
*/
-static struct cache_entry *refresh_entry(struct cache_entry *ce, int really)
+struct cache_entry *refresh_cache_entry(struct cache_entry *ce, int really)
{
struct stat st;
struct cache_entry *updated;
int changed, size;
- if (lstat(ce->name, &st) < 0)
- return ERR_PTR(-errno);
+ if (lstat(ce->name, &st) < 0) {
+ cache_errno = errno;
+ return NULL;
+ }
changed = ce_match_stat(ce, &st, really);
if (!changed) {
@@ -619,11 +610,13 @@ static struct cache_entry *refresh_entry(struct cache_entry *ce, int really)
!(ce->ce_flags & htons(CE_VALID)))
; /* mark this one VALID again */
else
- return NULL;
+ return ce;
}
- if (ce_modified(ce, &st, really))
- return ERR_PTR(-EINVAL);
+ if (ce_modified(ce, &st, really)) {
+ cache_errno = EINVAL;
+ return NULL;
+ }
size = ce_size(ce);
updated = xmalloc(size);
@@ -666,13 +659,13 @@ int refresh_cache(unsigned int flags)
continue;
}
- new = refresh_entry(ce, really);
- if (!new)
+ new = refresh_cache_entry(ce, really);
+ if (new == ce)
continue;
- if (IS_ERR(new)) {
- if (not_new && PTR_ERR(new) == -ENOENT)
+ if (!new) {
+ if (not_new && cache_errno == ENOENT)
continue;
- if (really && PTR_ERR(new) == -EINVAL) {
+ if (really && cache_errno == EINVAL) {
/* If we are doing --really-refresh that
* means the index is not valid anymore.
*/
@@ -729,39 +722,43 @@ static int read_index_extension(const char *ext, void *data, unsigned long sz)
int read_cache(void)
{
+ return read_cache_from(get_index_file());
+}
+
+/* remember to discard_cache() before reading a different cache! */
+int read_cache_from(const char *path)
+{
int fd, i;
struct stat st;
- unsigned long size, offset;
- void *map;
+ unsigned long offset;
struct cache_header *hdr;
errno = EBUSY;
- if (active_cache)
+ if (cache_mmap)
return active_nr;
errno = ENOENT;
index_file_timestamp = 0;
- fd = open(get_index_file(), O_RDONLY);
+ fd = open(path, O_RDONLY);
if (fd < 0) {
if (errno == ENOENT)
return 0;
die("index file open failed (%s)", strerror(errno));
}
- size = 0; /* avoid gcc warning */
- map = MAP_FAILED;
+ cache_mmap = MAP_FAILED;
if (!fstat(fd, &st)) {
- size = st.st_size;
+ cache_mmap_size = st.st_size;
errno = EINVAL;
- if (size >= sizeof(struct cache_header) + 20)
- map = mmap(NULL, size, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0);
+ if (cache_mmap_size >= sizeof(struct cache_header) + 20)
+ cache_mmap = mmap(NULL, cache_mmap_size, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0);
}
close(fd);
- if (map == MAP_FAILED)
+ if (cache_mmap == MAP_FAILED)
die("index file mmap failed (%s)", strerror(errno));
- hdr = map;
- if (verify_hdr(hdr, size) < 0)
+ hdr = cache_mmap;
+ if (verify_hdr(hdr, cache_mmap_size) < 0)
goto unmap;
active_nr = ntohl(hdr->hdr_entries);
@@ -770,12 +767,12 @@ int read_cache(void)
offset = sizeof(*hdr);
for (i = 0; i < active_nr; i++) {
- struct cache_entry *ce = (struct cache_entry *) ((char *) map + offset);
+ struct cache_entry *ce = (struct cache_entry *) ((char *) cache_mmap + offset);
offset = offset + ce_size(ce);
active_cache[i] = ce;
}
index_file_timestamp = st.st_mtime;
- while (offset <= size - 20 - 8) {
+ while (offset <= cache_mmap_size - 20 - 8) {
/* After an array of active_nr index entries,
* there can be arbitrary number of extended
* sections, each of which is prefixed with
@@ -783,10 +780,10 @@ int read_cache(void)
* in 4-byte network byte order.
*/
unsigned long extsize;
- memcpy(&extsize, (char *) map + offset + 4, 4);
+ memcpy(&extsize, (char *) cache_mmap + offset + 4, 4);
extsize = ntohl(extsize);
- if (read_index_extension(((const char *) map) + offset,
- (char *) map + offset + 8,
+ if (read_index_extension(((const char *) cache_mmap) + offset,
+ (char *) cache_mmap + offset + 8,
extsize) < 0)
goto unmap;
offset += 8;
@@ -795,11 +792,28 @@ int read_cache(void)
return active_nr;
unmap:
- munmap(map, size);
+ munmap(cache_mmap, cache_mmap_size);
errno = EINVAL;
die("index file corrupt");
}
+int discard_cache()
+{
+ int ret;
+
+ if (cache_mmap == NULL)
+ return 0;
+ ret = munmap(cache_mmap, cache_mmap_size);
+ cache_mmap = NULL;
+ cache_mmap_size = 0;
+ active_nr = active_cache_changed = 0;
+ index_file_timestamp = 0;
+ cache_tree_free(&active_cache_tree);
+
+ /* no need to throw away allocated active_cache */
+ return ret;
+}
+
#define WRITE_BUFFER_SIZE 8192
static unsigned char write_buffer[WRITE_BUFFER_SIZE];
static unsigned long write_buffer_len;