blob: 86e5f5dba55e42a54ecf4d14904ba49699d48a74 [file] [log] [blame]
/*
* Copyright (C) 2009-2011 the libgit2 contributors
*
* This file is part of libgit2, distributed under the GNU GPL v2 with
* a Linking Exception. For full terms see the included COPYING file.
*/
#include "refs.h"
#include "hash.h"
#include "repository.h"
#include "fileops.h"
#include "pack.h"
#include "reflog.h"
#include <git2/tag.h>
#include <git2/object.h>
#define MAX_NESTING_LEVEL 5
enum {
GIT_PACKREF_HAS_PEEL = 1,
GIT_PACKREF_WAS_LOOSE = 2
};
struct packref {
git_oid oid;
git_oid peel;
char flags;
char name[GIT_FLEX_ARRAY];
};
static const int default_table_size = 32;
static int reference_read(
git_fbuffer *file_content,
time_t *mtime,
const char *repo_path,
const char *ref_name,
int *updated);
/* loose refs */
static int loose_parse_symbolic(git_reference *ref, git_fbuffer *file_content);
static int loose_parse_oid(git_oid *ref, git_fbuffer *file_content);
static int loose_lookup(git_reference *ref);
static int loose_lookup_to_packfile(struct packref **ref_out,
git_repository *repo, const char *name);
static int loose_write(git_reference *ref);
/* packed refs */
static int packed_parse_peel(struct packref *tag_ref,
const char **buffer_out, const char *buffer_end);
static int packed_parse_oid(struct packref **ref_out,
const char **buffer_out, const char *buffer_end);
static int packed_load(git_repository *repo);
static int packed_loadloose(git_repository *repository);
static int packed_write_ref(struct packref *ref, git_filebuf *file);
static int packed_find_peel(git_repository *repo, struct packref *ref);
static int packed_remove_loose(git_repository *repo, git_vector *packing_list);
static int packed_sort(const void *a, const void *b);
static int packed_lookup(git_reference *ref);
static int packed_write(git_repository *repo);
/* internal helpers */
static int reference_available(git_repository *repo,
const char *ref, const char *old_ref);
static int reference_delete(git_reference *ref);
static int reference_lookup(git_reference *ref);
/* name normalization */
static int normalize_name(char *buffer_out, size_t out_size,
const char *name, int is_oid_ref);
void git_reference_free(git_reference *reference)
{
if (reference == NULL)
return;
git__free(reference->name);
reference->name = NULL;
if (reference->flags & GIT_REF_SYMBOLIC) {
git__free(reference->target.symbolic);
reference->target.symbolic = NULL;
}
git__free(reference);
}
static int reference_alloc(
git_reference **ref_out,
git_repository *repo,
const char *name)
{
git_reference *reference = NULL;
assert(ref_out && repo && name);
reference = git__malloc(sizeof(git_reference));
if (reference == NULL)
return GIT_ENOMEM;
memset(reference, 0x0, sizeof(git_reference));
reference->owner = repo;
reference->name = git__strdup(name);
if (reference->name == NULL) {
free(reference);
return GIT_ENOMEM;
}
*ref_out = reference;
return GIT_SUCCESS;
}
static int reference_read(git_fbuffer *file_content, time_t *mtime, const char *repo_path, const char *ref_name, int *updated)
{
git_buf path = GIT_BUF_INIT;
int error = GIT_SUCCESS;
assert(file_content && repo_path && ref_name);
/* Determine the full path of the file */
if ((error = git_buf_joinpath(&path, repo_path, ref_name)) == GIT_SUCCESS)
error = git_futils_readbuffer_updated(file_content, path.ptr, mtime, updated);
git_buf_free(&path);
return error;
}
static int loose_parse_symbolic(git_reference *ref, git_fbuffer *file_content)
{
const unsigned int header_len = strlen(GIT_SYMREF);
const char *refname_start;
char *eol;
refname_start = (const char *)file_content->data;
if (file_content->len < (header_len + 1))
return git__throw(GIT_EOBJCORRUPTED,
"Failed to parse loose reference. Object too short");
/*
* Assume we have already checked for the header
* before calling this function
*/
refname_start += header_len;
ref->target.symbolic = git__strdup(refname_start);
if (ref->target.symbolic == NULL)
return GIT_ENOMEM;
/* remove newline at the end of file */
eol = strchr(ref->target.symbolic, '\n');
if (eol == NULL)
return git__throw(GIT_EOBJCORRUPTED,
"Failed to parse loose reference. Missing EOL");
*eol = '\0';
if (eol[-1] == '\r')
eol[-1] = '\0';
return GIT_SUCCESS;
}
static int loose_parse_oid(git_oid *oid, git_fbuffer *file_content)
{
int error;
char *buffer;
buffer = (char *)file_content->data;
/* File format: 40 chars (OID) + newline */
if (file_content->len < GIT_OID_HEXSZ + 1)
return git__throw(GIT_EOBJCORRUPTED,
"Failed to parse loose reference. Reference too short");
if ((error = git_oid_fromstr(oid, buffer)) < GIT_SUCCESS)
return git__rethrow(GIT_EOBJCORRUPTED, "Failed to parse loose reference.");
buffer = buffer + GIT_OID_HEXSZ;
if (*buffer == '\r')
buffer++;
if (*buffer != '\n')
return git__throw(GIT_EOBJCORRUPTED,
"Failed to parse loose reference. Missing EOL");
return GIT_SUCCESS;
}
static git_rtype loose_guess_rtype(const git_buf *full_path)
{
git_fbuffer ref_file = GIT_FBUFFER_INIT;
git_rtype type;
type = GIT_REF_INVALID;
if (git_futils_readbuffer(&ref_file, full_path->ptr) == GIT_SUCCESS) {
if (git__prefixcmp((const char *)(ref_file.data), GIT_SYMREF) == 0)
type = GIT_REF_SYMBOLIC;
else
type = GIT_REF_OID;
}
git_futils_freebuffer(&ref_file);
return type;
}
static int loose_lookup(git_reference *ref)
{
int error = GIT_SUCCESS, updated;
git_fbuffer ref_file = GIT_FBUFFER_INIT;
if (reference_read(&ref_file, &ref->mtime,
ref->owner->path_repository, ref->name, &updated) < GIT_SUCCESS)
return git__throw(GIT_ENOTFOUND, "Failed to lookup loose reference");
if (!updated)
return GIT_SUCCESS;
if (ref->flags & GIT_REF_SYMBOLIC) {
free(ref->target.symbolic);
ref->target.symbolic = NULL;
}
ref->flags = 0;
if (git__prefixcmp((const char *)(ref_file.data), GIT_SYMREF) == 0) {
ref->flags |= GIT_REF_SYMBOLIC;
error = loose_parse_symbolic(ref, &ref_file);
} else {
ref->flags |= GIT_REF_OID;
error = loose_parse_oid(&ref->target.oid, &ref_file);
}
git_futils_freebuffer(&ref_file);
if (error < GIT_SUCCESS)
return git__rethrow(error, "Failed to lookup loose reference");
return GIT_SUCCESS;
}
static int loose_lookup_to_packfile(
struct packref **ref_out,
git_repository *repo,
const char *name)
{
int error = GIT_SUCCESS;
git_fbuffer ref_file = GIT_FBUFFER_INIT;
struct packref *ref = NULL;
size_t name_len;
*ref_out = NULL;
error = reference_read(&ref_file, NULL, repo->path_repository, name, NULL);
if (error < GIT_SUCCESS)
goto cleanup;
name_len = strlen(name);
ref = git__malloc(sizeof(struct packref) + name_len + 1);
memcpy(ref->name, name, name_len);
ref->name[name_len] = 0;
error = loose_parse_oid(&ref->oid, &ref_file);
if (error < GIT_SUCCESS)
goto cleanup;
ref->flags = GIT_PACKREF_WAS_LOOSE;
*ref_out = ref;
git_futils_freebuffer(&ref_file);
return GIT_SUCCESS;
cleanup:
git_futils_freebuffer(&ref_file);
free(ref);
return git__rethrow(error, "Failed to lookup loose reference");
}
static int loose_write(git_reference *ref)
{
git_filebuf file = GIT_FILEBUF_INIT;
git_buf ref_path = GIT_BUF_INIT;
int error;
struct stat st;
error = git_buf_joinpath(&ref_path, ref->owner->path_repository, ref->name);
if (error < GIT_SUCCESS)
goto unlock;
error = git_filebuf_open(&file, ref_path.ptr, GIT_FILEBUF_FORCE);
if (error < GIT_SUCCESS)
goto unlock;
if (ref->flags & GIT_REF_OID) {
char oid[GIT_OID_HEXSZ + 1];
git_oid_fmt(oid, &ref->target.oid);
oid[GIT_OID_HEXSZ] = '\0';
error = git_filebuf_printf(&file, "%s\n", oid);
if (error < GIT_SUCCESS)
goto unlock;
} else if (ref->flags & GIT_REF_SYMBOLIC) { /* GIT_REF_SYMBOLIC */
error = git_filebuf_printf(&file, GIT_SYMREF "%s\n", ref->target.symbolic);
} else {
error = git__throw(GIT_EOBJCORRUPTED,
"Failed to write reference. Invalid reference type");
goto unlock;
}
if (p_stat(ref_path.ptr, &st) == GIT_SUCCESS)
ref->mtime = st.st_mtime;
git_buf_free(&ref_path);
return git_filebuf_commit(&file, GIT_REFS_FILE_MODE);
unlock:
git_buf_free(&ref_path);
git_filebuf_cleanup(&file);
return git__rethrow(error, "Failed to write loose reference");
}
static int packed_parse_peel(
struct packref *tag_ref,
const char **buffer_out,
const char *buffer_end)
{
const char *buffer = *buffer_out + 1;
assert(buffer[-1] == '^');
/* Ensure it's not the first entry of the file */
if (tag_ref == NULL)
return git__throw(GIT_EPACKEDREFSCORRUPTED,
"Failed to parse packed reference. "
"Reference is the first entry of the file");
/* Ensure reference is a tag */
if (git__prefixcmp(tag_ref->name, GIT_REFS_TAGS_DIR) != 0)
return git__throw(GIT_EPACKEDREFSCORRUPTED,
"Failed to parse packed reference. Reference is not a tag");
if (buffer + GIT_OID_HEXSZ >= buffer_end)
return git__throw(GIT_EPACKEDREFSCORRUPTED,
"Failed to parse packed reference. Buffer too small");
/* Is this a valid object id? */
if (git_oid_fromstr(&tag_ref->peel, buffer) < GIT_SUCCESS)
return git__throw(GIT_EPACKEDREFSCORRUPTED,
"Failed to parse packed reference. Not a valid object ID");
buffer = buffer + GIT_OID_HEXSZ;
if (*buffer == '\r')
buffer++;
if (*buffer != '\n')
return git__throw(GIT_EPACKEDREFSCORRUPTED,
"Failed to parse packed reference. Buffer not terminated correctly");
*buffer_out = buffer + 1;
return GIT_SUCCESS;
}
static int packed_parse_oid(
struct packref **ref_out,
const char **buffer_out,
const char *buffer_end)
{
struct packref *ref = NULL;
const char *buffer = *buffer_out;
const char *refname_begin, *refname_end;
int error = GIT_SUCCESS;
size_t refname_len;
git_oid id;
refname_begin = (buffer + GIT_OID_HEXSZ + 1);
if (refname_begin >= buffer_end ||
refname_begin[-1] != ' ') {
error = GIT_EPACKEDREFSCORRUPTED;
goto cleanup;
}
/* Is this a valid object id? */
if ((error = git_oid_fromstr(&id, buffer)) < GIT_SUCCESS)
goto cleanup;
refname_end = memchr(refname_begin, '\n', buffer_end - refname_begin);
if (refname_end == NULL) {
error = GIT_EPACKEDREFSCORRUPTED;
goto cleanup;
}
if (refname_end[-1] == '\r')
refname_end--;
refname_len = refname_end - refname_begin;
ref = git__malloc(sizeof(struct packref) + refname_len + 1);
memcpy(ref->name, refname_begin, refname_len);
ref->name[refname_len] = 0;
git_oid_cpy(&ref->oid, &id);
ref->flags = 0;
*ref_out = ref;
*buffer_out = refname_end + 1;
return GIT_SUCCESS;
cleanup:
free(ref);
return git__rethrow(error, "Failed to parse OID of packed reference");
}
static int packed_load(git_repository *repo)
{
int error = GIT_SUCCESS, updated;
git_fbuffer packfile = GIT_FBUFFER_INIT;
const char *buffer_start, *buffer_end;
git_refcache *ref_cache = &repo->references;
/* First we make sure we have allocated the hash table */
if (ref_cache->packfile == NULL) {
ref_cache->packfile = git_hashtable_alloc(
default_table_size, git_hash__strhash_cb, git_hash__strcmp_cb);
if (ref_cache->packfile == NULL) {
error = GIT_ENOMEM;
goto cleanup;
}
}
error = reference_read(&packfile, &ref_cache->packfile_time,
repo->path_repository, GIT_PACKEDREFS_FILE, &updated);
/*
* If we couldn't find the file, we need to clear the table and
* return. On any other error, we return that error. If everything
* went fine and the file wasn't updated, then there's nothing new
* for us here, so just return. Anything else means we need to
* refresh the packed refs.
*/
if (error == GIT_ENOTFOUND) {
git_hashtable_clear(ref_cache->packfile);
return GIT_SUCCESS;
} else if (error < GIT_SUCCESS) {
return git__rethrow(error, "Failed to read packed refs");
} else if (!updated) {
return GIT_SUCCESS;
}
/*
* At this point, we want to refresh the packed refs. We already
* have the contents in our buffer.
*/
git_hashtable_clear(ref_cache->packfile);
buffer_start = (const char *)packfile.data;
buffer_end = (const char *)(buffer_start) + packfile.len;
while (buffer_start < buffer_end && buffer_start[0] == '#') {
buffer_start = strchr(buffer_start, '\n');
if (buffer_start == NULL) {
error = GIT_EPACKEDREFSCORRUPTED;
goto cleanup;
}
buffer_start++;
}
while (buffer_start < buffer_end) {
struct packref *ref = NULL;
error = packed_parse_oid(&ref, &buffer_start, buffer_end);
if (error < GIT_SUCCESS)
goto cleanup;
if (buffer_start[0] == '^') {
error = packed_parse_peel(ref, &buffer_start, buffer_end);
if (error < GIT_SUCCESS)
goto cleanup;
}
error = git_hashtable_insert(ref_cache->packfile, ref->name, ref);
if (error < GIT_SUCCESS) {
free(ref);
goto cleanup;
}
}
git_futils_freebuffer(&packfile);
return GIT_SUCCESS;
cleanup:
git_hashtable_free(ref_cache->packfile);
ref_cache->packfile = NULL;
git_futils_freebuffer(&packfile);
return git__rethrow(error, "Failed to load packed references");
}
struct dirent_list_data {
git_repository *repo;
size_t repo_path_len;
unsigned int list_flags;
int (*callback)(const char *, void *);
void *callback_payload;
};
static int _dirent_loose_listall(void *_data, git_buf *full_path)
{
struct dirent_list_data *data = (struct dirent_list_data *)_data;
const char *file_path = full_path->ptr + data->repo_path_len;
if (git_path_isdir(full_path->ptr) == GIT_SUCCESS)
return git_path_direach(full_path, _dirent_loose_listall, _data);
/* do not add twice a reference that exists already in the packfile */
if ((data->list_flags & GIT_REF_PACKED) != 0 &&
git_hashtable_lookup(data->repo->references.packfile, file_path) != NULL)
return GIT_SUCCESS;
if (data->list_flags != GIT_REF_LISTALL) {
if ((data->list_flags & loose_guess_rtype(full_path)) == 0)
return GIT_SUCCESS; /* we are filtering out this reference */
}
return data->callback(file_path, data->callback_payload);
}
static int _dirent_loose_load(void *data, git_buf *full_path)
{
git_repository *repository = (git_repository *)data;
void *old_ref = NULL;
struct packref *ref;
const char *file_path;
int error;
if (git_path_isdir(full_path->ptr) == GIT_SUCCESS)
return git_path_direach(full_path, _dirent_loose_load, repository);
file_path = full_path->ptr + strlen(repository->path_repository);
error = loose_lookup_to_packfile(&ref, repository, file_path);
if (error == GIT_SUCCESS) {
if (git_hashtable_insert2(
repository->references.packfile,
ref->name, ref, &old_ref) < GIT_SUCCESS) {
free(ref);
return GIT_ENOMEM;
}
if (old_ref != NULL)
free(old_ref);
}
return error == GIT_SUCCESS ?
GIT_SUCCESS :
git__rethrow(error, "Failed to load loose references into packfile");
}
/*
* Load all the loose references from the repository
* into the in-memory Packfile, and build a vector with
* all the references so it can be written back to
* disk.
*/
static int packed_loadloose(git_repository *repository)
{
int error = GIT_SUCCESS;
git_buf refs_path = GIT_BUF_INIT;
/* the packfile must have been previously loaded! */
assert(repository->references.packfile);
if ((error = git_buf_joinpath(&refs_path,
repository->path_repository, GIT_REFS_DIR)) < GIT_SUCCESS)
return error;
/*
* Load all the loose files from disk into the Packfile table.
* This will overwrite any old packed entries with their
* updated loose versions
*/
error = git_path_direach(&refs_path, _dirent_loose_load, repository);
git_buf_free(&refs_path);
return error;
}
/*
* Write a single reference into a packfile
*/
static int packed_write_ref(struct packref *ref, git_filebuf *file)
{
int error;
char oid[GIT_OID_HEXSZ + 1];
git_oid_fmt(oid, &ref->oid);
oid[GIT_OID_HEXSZ] = 0;
/*
* For references that peel to an object in the repo, we must
* write the resulting peel on a separate line, e.g.
*
* 6fa8a902cc1d18527e1355773c86721945475d37 refs/tags/libgit2-0.4
* ^2ec0cb7959b0bf965d54f95453f5b4b34e8d3100
*
* This obviously only applies to tags.
* The required peels have already been loaded into `ref->peel_target`.
*/
if (ref->flags & GIT_PACKREF_HAS_PEEL) {
char peel[GIT_OID_HEXSZ + 1];
git_oid_fmt(peel, &ref->peel);
peel[GIT_OID_HEXSZ] = 0;
error = git_filebuf_printf(file, "%s %s\n^%s\n", oid, ref->name, peel);
} else {
error = git_filebuf_printf(file, "%s %s\n", oid, ref->name);
}
return error == GIT_SUCCESS ?
GIT_SUCCESS :
git__rethrow(error, "Failed to write packed reference");
}
/*
* Find out what object this reference resolves to.
*
* For references that point to a 'big' tag (e.g. an
* actual tag object on the repository), we need to
* cache on the packfile the OID of the object to
* which that 'big tag' is pointing to.
*/
static int packed_find_peel(git_repository *repo, struct packref *ref)
{
git_object *object;
int error;
if (ref->flags & GIT_PACKREF_HAS_PEEL)
return GIT_SUCCESS;
/*
* Only applies to tags, i.e. references
* in the /refs/tags folder
*/
if (git__prefixcmp(ref->name, GIT_REFS_TAGS_DIR) != 0)
return GIT_SUCCESS;
/*
* Find the tagged object in the repository
*/
error = git_object_lookup(&object, repo, &ref->oid, GIT_OBJ_ANY);
if (error < GIT_SUCCESS)
return git__throw(GIT_EOBJCORRUPTED, "Failed to find packed reference");
/*
* If the tagged object is a Tag object, we need to resolve it;
* if the ref is actually a 'weak' ref, we don't need to resolve
* anything.
*/
if (git_object_type(object) == GIT_OBJ_TAG) {
git_tag *tag = (git_tag *)object;
/*
* Find the object pointed at by this tag
*/
git_oid_cpy(&ref->peel, git_tag_target_oid(tag));
ref->flags |= GIT_PACKREF_HAS_PEEL;
/*
* The reference has now cached the resolved OID, and is
* marked at such. When written to the packfile, it'll be
* accompanied by this resolved oid
*/
}
git_object_free(object);
return GIT_SUCCESS;
}
/*
* Remove all loose references
*
* Once we have successfully written a packfile,
* all the loose references that were packed must be
* removed from disk.
*
* This is a dangerous method; make sure the packfile
* is well-written, because we are destructing references
* here otherwise.
*/
static int packed_remove_loose(git_repository *repo, git_vector *packing_list)
{
unsigned int i;
git_buf full_path = GIT_BUF_INIT;
int error = GIT_SUCCESS;
for (i = 0; i < packing_list->length; ++i) {
struct packref *ref = git_vector_get(packing_list, i);
int an_error;
if ((ref->flags & GIT_PACKREF_WAS_LOOSE) == 0)
continue;
an_error = git_buf_joinpath(&full_path, repo->path_repository, ref->name);
if (an_error == GIT_SUCCESS &&
git_path_exists(full_path.ptr) == GIT_SUCCESS &&
p_unlink(full_path.ptr) < GIT_SUCCESS)
an_error = GIT_EOSERR;
/* keep the error if we haven't seen one yet */
if (error > an_error)
error = an_error;
/*
* if we fail to remove a single file, this is *not* good,
* but we should keep going and remove as many as possible.
* After we've removed as many files as possible, we return
* the error code anyway.
*/
}
git_buf_free(&full_path);
return error == GIT_SUCCESS ?
GIT_SUCCESS :
git__rethrow(error, "Failed to remove loose packed reference");
}
static int packed_sort(const void *a, const void *b)
{
const struct packref *ref_a = (const struct packref *)a;
const struct packref *ref_b = (const struct packref *)b;
return strcmp(ref_a->name, ref_b->name);
}
/*
* Write all the contents in the in-memory packfile to disk.
*/
static int packed_write(git_repository *repo)
{
git_filebuf pack_file = GIT_FILEBUF_INIT;
int error;
const char *errmsg = "Failed to write packed references file";
unsigned int i;
git_buf pack_file_path = GIT_BUF_INIT;
git_vector packing_list;
size_t total_refs;
assert(repo && repo->references.packfile);
total_refs = repo->references.packfile->key_count;
if ((error =
git_vector_init(&packing_list, total_refs, packed_sort)) < GIT_SUCCESS)
return git__rethrow(error, "Failed to init packed references list");
/* Load all the packfile into a vector */
{
struct packref *reference;
const void *GIT_UNUSED(_unused);
GIT_HASHTABLE_FOREACH(repo->references.packfile, _unused, reference,
/* cannot fail: vector already has the right size */
git_vector_insert(&packing_list, reference);
);
}
/* sort the vector so the entries appear sorted on the packfile */
git_vector_sort(&packing_list);
/* Now we can open the file! */
error = git_buf_joinpath(&pack_file_path, repo->path_repository, GIT_PACKEDREFS_FILE);
if (error < GIT_SUCCESS)
goto cleanup;
if ((error = git_filebuf_open(&pack_file, pack_file_path.ptr, 0)) < GIT_SUCCESS) {
errmsg = "Failed to open packed references file";
goto cleanup;
}
/* Packfiles have a header... apparently
* This is in fact not required, but we might as well print it
* just for kicks */
if ((error =
git_filebuf_printf(&pack_file, "%s\n", GIT_PACKEDREFS_HEADER)) < GIT_SUCCESS) {
errmsg = "Failed to write packed references file header";
goto cleanup;
}
for (i = 0; i < packing_list.length; ++i) {
struct packref *ref = (struct packref *)git_vector_get(&packing_list, i);
if ((error = packed_find_peel(repo, ref)) < GIT_SUCCESS) {
error = git__throw(GIT_EOBJCORRUPTED,
"A reference cannot be peeled");
goto cleanup;
}
if ((error = packed_write_ref(ref, &pack_file)) < GIT_SUCCESS)
goto cleanup;
}
cleanup:
/* if we've written all the references properly, we can commit
* the packfile to make the changes effective */
if (error == GIT_SUCCESS) {
error = git_filebuf_commit(&pack_file, GIT_PACKEDREFS_FILE_MODE);
/* when and only when the packfile has been properly written,
* we can go ahead and remove the loose refs */
if (error == GIT_SUCCESS) {
struct stat st;
error = packed_remove_loose(repo, &packing_list);
if (p_stat(pack_file_path.ptr, &st) == GIT_SUCCESS)
repo->references.packfile_time = st.st_mtime;
}
}
else git_filebuf_cleanup(&pack_file);
git_vector_free(&packing_list);
git_buf_free(&pack_file_path);
if (error < GIT_SUCCESS)
git__rethrow(error, "%s", errmsg);
return error;
}
static int _reference_available_cb(const char *ref, void *data)
{
const char *new, *old;
const char **refs;
assert(ref && data);
refs = (const char **)data;
new = (const char *)refs[0];
old = (const char *)refs[1];
if (!old || strcmp(old, ref)) {
int reflen = strlen(ref);
int newlen = strlen(new);
int cmplen = reflen < newlen ? reflen : newlen;
const char *lead = reflen < newlen ? new : ref;
if (!strncmp(new, ref, cmplen) &&
lead[cmplen] == '/')
return GIT_EEXISTS;
}
return GIT_SUCCESS;
}
static int reference_available(
git_repository *repo,
const char *ref,
const char* old_ref)
{
const char *refs[2];
refs[0] = ref;
refs[1] = old_ref;
if (git_reference_foreach(repo, GIT_REF_LISTALL,
_reference_available_cb, (void *)refs) < 0) {
return git__throw(GIT_EEXISTS,
"Reference name `%s` conflicts with existing reference", ref);
}
return GIT_SUCCESS;
}
static int reference_exists(int *exists, git_repository *repo, const char *ref_name)
{
int error;
git_buf ref_path = GIT_BUF_INIT;
error = packed_load(repo);
if (error < GIT_SUCCESS)
return git__rethrow(error, "Cannot resolve if a reference exists");
error = git_buf_joinpath(&ref_path, repo->path_repository, ref_name);
if (error < GIT_SUCCESS)
return git__rethrow(error, "Cannot resolve if a reference exists");
if (git_path_isfile(ref_path.ptr) == GIT_SUCCESS ||
git_hashtable_lookup(repo->references.packfile, ref_path.ptr) != NULL) {
*exists = 1;
} else {
*exists = 0;
}
git_buf_free(&ref_path);
return GIT_SUCCESS;
}
static int packed_lookup(git_reference *ref)
{
int error;
struct packref *pack_ref = NULL;
error = packed_load(ref->owner);
if (error < GIT_SUCCESS)
return git__rethrow(error,
"Failed to lookup reference from packfile");
if (ref->flags & GIT_REF_PACKED &&
ref->mtime == ref->owner->references.packfile_time)
return GIT_SUCCESS;
if (ref->flags & GIT_REF_SYMBOLIC) {
free(ref->target.symbolic);
ref->target.symbolic = NULL;
}
/* Look up on the packfile */
pack_ref = git_hashtable_lookup(ref->owner->references.packfile, ref->name);
if (pack_ref == NULL)
return git__throw(GIT_ENOTFOUND,
"Failed to lookup reference from packfile");
ref->flags = GIT_REF_OID | GIT_REF_PACKED;
ref->mtime = ref->owner->references.packfile_time;
git_oid_cpy(&ref->target.oid, &pack_ref->oid);
return GIT_SUCCESS;
}
static int reference_lookup(git_reference *ref)
{
int error_loose, error_packed;
error_loose = loose_lookup(ref);
if (error_loose == GIT_SUCCESS)
return GIT_SUCCESS;
error_packed = packed_lookup(ref);
if (error_packed == GIT_SUCCESS)
return GIT_SUCCESS;
git_reference_free(ref);
if (error_loose != GIT_ENOTFOUND)
return git__rethrow(error_loose, "Failed to lookup reference");
if (error_packed != GIT_ENOTFOUND)
return git__rethrow(error_packed, "Failed to lookup reference");
return git__throw(GIT_ENOTFOUND, "Reference not found");
}
/*
* Delete a reference.
* This is an internal method; the reference is removed
* from disk or the packfile, but the pointer is not freed
*/
static int reference_delete(git_reference *ref)
{
int error;
assert(ref);
/* If the reference is packed, this is an expensive operation.
* We need to reload the packfile, remove the reference from the
* packing list, and repack */
if (ref->flags & GIT_REF_PACKED) {
struct packref *packref;
/* load the existing packfile */
if ((error = packed_load(ref->owner)) < GIT_SUCCESS)
return git__rethrow(error, "Failed to delete reference");
if (git_hashtable_remove2(ref->owner->references.packfile,
ref->name, (void **) &packref) < GIT_SUCCESS)
return git__throw(GIT_ENOTFOUND, "Reference not found");
git__free (packref);
error = packed_write(ref->owner);
/* If the reference is loose, we can just remove the reference
* from the filesystem */
} else {
git_reference *ref_in_pack;
git_buf full_path = GIT_BUF_INIT;
error = git_buf_joinpath(&full_path, ref->owner->path_repository, ref->name);
if (error < GIT_SUCCESS)
goto cleanup;
error = p_unlink(full_path.ptr);
git_buf_free(&full_path); /* done with path at this point */
if (error < GIT_SUCCESS)
goto cleanup;
/* When deleting a loose reference, we have to ensure that an older
* packed version of it doesn't exist */
if (git_reference_lookup(&ref_in_pack, ref->owner,
ref->name) == GIT_SUCCESS) {
assert((ref_in_pack->flags & GIT_REF_PACKED) != 0);
error = git_reference_delete(ref_in_pack);
}
}
cleanup:
return error == GIT_SUCCESS ?
GIT_SUCCESS :
git__rethrow(error, "Failed to delete reference");
}
int git_reference_delete(git_reference *ref)
{
int error = reference_delete(ref);
if (error < GIT_SUCCESS)
return error;
git_reference_free(ref);
return GIT_SUCCESS;
}
int git_reference_lookup(git_reference **ref_out,
git_repository *repo, const char *name)
{
int error;
char normalized_name[GIT_REFNAME_MAX];
git_reference *ref = NULL;
assert(ref_out && repo && name);
*ref_out = NULL;
error = normalize_name(normalized_name, sizeof(normalized_name), name, 0);
if (error < GIT_SUCCESS)
return git__rethrow(error, "Failed to lookup reference");
error = reference_alloc(&ref, repo, normalized_name);
if (error < GIT_SUCCESS)
return git__rethrow(error, "Failed to lookup reference");
error = reference_lookup(ref);
if (error < GIT_SUCCESS)
return git__rethrow(error, "Failed to lookup reference");
*ref_out = ref;
return GIT_SUCCESS;
}
/**
* Getters
*/
git_rtype git_reference_type(git_reference *ref)
{
assert(ref);
if (ref->flags & GIT_REF_OID)
return GIT_REF_OID;
if (ref->flags & GIT_REF_SYMBOLIC)
return GIT_REF_SYMBOLIC;
return GIT_REF_INVALID;
}
int git_reference_is_packed(git_reference *ref)
{
assert(ref);
return !!(ref->flags & GIT_REF_PACKED);
}
const char *git_reference_name(git_reference *ref)
{
assert(ref);
return ref->name;
}
git_repository *git_reference_owner(git_reference *ref)
{
assert(ref);
return ref->owner;
}
const git_oid *git_reference_oid(git_reference *ref)
{
assert(ref);
if ((ref->flags & GIT_REF_OID) == 0)
return NULL;
return &ref->target.oid;
}
const char *git_reference_target(git_reference *ref)
{
assert(ref);
if ((ref->flags & GIT_REF_SYMBOLIC) == 0)
return NULL;
return ref->target.symbolic;
}
int git_reference_create_symbolic(
git_reference **ref_out,
git_repository *repo,
const char *name,
const char *target,
int force)
{
char normalized[GIT_REFNAME_MAX];
int ref_exists, error = GIT_SUCCESS;
git_reference *ref = NULL;
error = normalize_name(normalized, sizeof(normalized), name, 0);
if (error < GIT_SUCCESS)
goto cleanup;
if ((error = reference_exists(&ref_exists, repo, normalized) < GIT_SUCCESS))
return git__rethrow(error, "Failed to create symbolic reference");
if (ref_exists && !force)
return git__throw(GIT_EEXISTS,
"Failed to create symbolic reference. Reference already exists");
error = reference_alloc(&ref, repo, normalized);
if (error < GIT_SUCCESS)
goto cleanup;
ref->flags |= GIT_REF_SYMBOLIC;
/* set the target; this will normalize the name automatically
* and write the reference on disk */
error = git_reference_set_target(ref, target);
if (error < GIT_SUCCESS)
goto cleanup;
if (ref_out == NULL) {
git_reference_free(ref);
} else {
*ref_out = ref;
}
return GIT_SUCCESS;
cleanup:
git_reference_free(ref);
return git__rethrow(error, "Failed to create symbolic reference");
}
int git_reference_create_oid(
git_reference **ref_out,
git_repository *repo,
const char *name,
const git_oid *id,
int force)
{
int error = GIT_SUCCESS, ref_exists;
git_reference *ref = NULL;
char normalized[GIT_REFNAME_MAX];
error = normalize_name(normalized, sizeof(normalized), name, 1);
if (error < GIT_SUCCESS)
goto cleanup;
if ((error = reference_exists(&ref_exists, repo, normalized) < GIT_SUCCESS))
return git__rethrow(error, "Failed to create OID reference");
if (ref_exists && !force)
return git__throw(GIT_EEXISTS,
"Failed to create OID reference. Reference already exists");
if ((error = reference_available(repo, name, NULL)) < GIT_SUCCESS)
return git__rethrow(error, "Failed to create reference");
error = reference_alloc(&ref, repo, name);
if (error < GIT_SUCCESS)
goto cleanup;
ref->flags |= GIT_REF_OID;
/* set the oid; this will write the reference on disk */
error = git_reference_set_oid(ref, id);
if (error < GIT_SUCCESS)
goto cleanup;
if (ref_out == NULL) {
git_reference_free(ref);
} else {
*ref_out = ref;
}
return GIT_SUCCESS;
cleanup:
git_reference_free(ref);
return git__rethrow(error, "Failed to create reference OID");
}
/*
* Change the OID target of a reference.
*
* For both loose and packed references, just change
* the oid in memory and (over)write the file in disk.
*
* We do not repack packed references because of performance
* reasons.
*/
int git_reference_set_oid(git_reference *ref, const git_oid *id)
{
int error = GIT_SUCCESS, exists;
git_odb *odb = NULL;
if ((ref->flags & GIT_REF_OID) == 0)
return git__throw(GIT_EINVALIDREFSTATE,
"Failed to set OID target of reference. Not an OID reference");
assert(ref->owner);
error = git_repository_odb__weakptr(&odb, ref->owner);
if (error < GIT_SUCCESS)
return error;
exists = git_odb_exists(odb, id);
git_odb_free(odb);
/* Don't let the user create references to OIDs that
* don't exist in the ODB */
if (!exists)
return git__throw(GIT_ENOTFOUND,
"Failed to set OID target of reference. OID doesn't exist in ODB");
/* Update the OID value on `ref` */
git_oid_cpy(&ref->target.oid, id);
/* Write back to disk */
error = loose_write(ref);
if (error < GIT_SUCCESS)
return git__rethrow(error, "Failed to set OID target of reference");
return GIT_SUCCESS;
}
/*
* Change the target of a symbolic reference.
*
* This is easy because symrefs cannot be inside
* a pack. We just change the target in memory
* and overwrite the file on disk.
*/
int git_reference_set_target(git_reference *ref, const char *target)
{
int error;
char normalized[GIT_REFNAME_MAX];
if ((ref->flags & GIT_REF_SYMBOLIC) == 0)
return git__throw(GIT_EINVALIDREFSTATE,
"Failed to set reference target. Not a symbolic reference");
error = normalize_name(normalized, sizeof(normalized), target, 0);
if (error < GIT_SUCCESS)
return git__rethrow(error,
"Failed to set reference target. Invalid target name");
git__free(ref->target.symbolic);
ref->target.symbolic = git__strdup(normalized);
if (ref->target.symbolic == NULL)
return GIT_ENOMEM;
return loose_write(ref);
}
int git_reference_rename(git_reference *ref, const char *new_name, int force)
{
int error;
git_buf aux_path = GIT_BUF_INIT;
char normalized[GIT_REFNAME_MAX];
const char *head_target = NULL;
git_reference *existing_ref = NULL, *head = NULL;
error = normalize_name(normalized, sizeof(normalized),
new_name, ref->flags & GIT_REF_OID);
if (error < GIT_SUCCESS)
return git__rethrow(error, "Failed to rename reference. Invalid name");
new_name = normalized;
/* If we are forcing the rename, try to lookup a reference with the
* new one. If the lookup succeeds, we need to delete that ref
* before the renaming can proceed */
if (force) {
error = git_reference_lookup(&existing_ref, ref->owner, new_name);
if (error == GIT_SUCCESS) {
error = git_reference_delete(existing_ref);
if (error < GIT_SUCCESS)
return git__rethrow(error,
"Failed to rename reference. "
"The existing reference cannot be deleted");
} else if (error != GIT_ENOTFOUND)
goto cleanup;
/* If we're not forcing the rename, check if the reference exists.
* If it does, renaming cannot continue */
} else {
int exists;
error = reference_exists(&exists, ref->owner, normalized);
if (error < GIT_SUCCESS)
goto cleanup;
if (exists)
return git__throw(GIT_EEXISTS,
"Failed to rename reference. Reference already exists");
}
if ((error = reference_available(ref->owner, new_name, ref->name)) < GIT_SUCCESS)
return git__rethrow(error,
"Failed to rename reference. Reference already exists");
/* Initialize path now so we won't get an allocation failure once
* we actually start removing things.
*/
error = git_buf_joinpath(&aux_path, ref->owner->path_repository, new_name);
if (error < GIT_SUCCESS)
goto cleanup;
/*
* Now delete the old ref and remove an possibly existing directory
* named `new_name`. Note that using the internal `reference_delete`
* method deletes the ref from disk but doesn't free the pointer, so
* we can still access the ref's attributes for creating the new one
*/
if ((error = reference_delete(ref)) < GIT_SUCCESS)
goto cleanup;
if (git_path_exists(aux_path.ptr) == GIT_SUCCESS) {
if (git_path_isdir(aux_path.ptr) == GIT_SUCCESS) {
if ((error = git_futils_rmdir_r(aux_path.ptr, 0)) < GIT_SUCCESS)
goto rollback;
} else goto rollback;
}
/*
* Finally we can create the new reference.
*/
if (ref->flags & GIT_REF_SYMBOLIC) {
error = git_reference_create_symbolic(
NULL, ref->owner, new_name, ref->target.symbolic, 0);
} else {
error = git_reference_create_oid(
NULL, ref->owner, new_name, &ref->target.oid, 0);
}
if (error < GIT_SUCCESS)
goto rollback;
/*
* Check if we have to update HEAD.
*/
error = git_reference_lookup(&head, ref->owner, GIT_HEAD_FILE);
if (error < GIT_SUCCESS)
goto cleanup;
head_target = git_reference_target(head);
if (head_target && !strcmp(head_target, ref->name)) {
error = git_reference_create_symbolic(
&head, ref->owner, "HEAD", new_name, 1);
if (error < GIT_SUCCESS)
goto cleanup;
}
/*
* Rename the reflog file.
*/
error = git_buf_join_n(&aux_path, '/', 3, ref->owner->path_repository,
GIT_REFLOG_DIR, ref->name);
if (error < GIT_SUCCESS)
goto cleanup;
if (git_path_exists(aux_path.ptr) == GIT_SUCCESS)
error = git_reflog_rename(ref, new_name);
/*
* Change the name of the reference given by the user.
*/
git__free(ref->name);
ref->name = git__strdup(new_name);
/* The reference is no longer packed */
ref->flags &= ~GIT_REF_PACKED;
cleanup:
/* We no longer need the newly created reference nor the head */
git_reference_free(head);
git_buf_free(&aux_path);
return error == GIT_SUCCESS ?
GIT_SUCCESS :
git__rethrow(error, "Failed to rename reference");
rollback:
/*
* Try to create the old reference again.
*/
if (ref->flags & GIT_REF_SYMBOLIC)
error = git_reference_create_symbolic(
NULL, ref->owner, ref->name, ref->target.symbolic, 0);
else
error = git_reference_create_oid(
NULL, ref->owner, ref->name, &ref->target.oid, 0);
/* The reference is no longer packed */
ref->flags &= ~GIT_REF_PACKED;
git_buf_free(&aux_path);
return error == GIT_SUCCESS ?
git__rethrow(GIT_ERROR, "Failed to rename reference. Did rollback") :
git__rethrow(error, "Failed to rename reference. Failed to rollback");
}
int git_reference_resolve(git_reference **ref_out, git_reference *ref)
{
int error, i = 0;
git_repository *repo;
assert(ref);
*ref_out = NULL;
repo = ref->owner;
/* If the reference is already resolved, we need to return a
* copy. Instead of duplicating `ref`, we look it up again to
* ensure the copy is out to date */
if (ref->flags & GIT_REF_OID)
return git_reference_lookup(ref_out, ref->owner, ref->name);
/* Otherwise, keep iterating until the reference is resolved */
for (i = 0; i < MAX_NESTING_LEVEL; ++i) {
git_reference *new_ref;
error = git_reference_lookup(&new_ref, repo, ref->target.symbolic);
if (error < GIT_SUCCESS)
return git__rethrow(error, "Failed to resolve reference");
/* Free intermediate references, except for the original one
* we've received */
if (i > 0)
git_reference_free(ref);
ref = new_ref;
/* When the reference we've just looked up is an OID, we've
* successfully resolved the symbolic ref */
if (ref->flags & GIT_REF_OID) {
*ref_out = ref;
return GIT_SUCCESS;
}
}
return git__throw(GIT_ENOMEM,
"Failed to resolve reference. Reference is too nested");
}
int git_reference_packall(git_repository *repo)
{
int error;
/* load the existing packfile */
if ((error = packed_load(repo)) < GIT_SUCCESS)
return git__rethrow(error, "Failed to pack references");
/* update it in-memory with all the loose references */
if ((error = packed_loadloose(repo)) < GIT_SUCCESS)
return git__rethrow(error, "Failed to pack references");
/* write it back to disk */
return packed_write(repo);
}
int git_reference_foreach(
git_repository *repo,
unsigned int list_flags,
int (*callback)(const char *, void *),
void *payload)
{
int error;
struct dirent_list_data data;
git_buf refs_path = GIT_BUF_INIT;
/* list all the packed references first */
if (list_flags & GIT_REF_PACKED) {
const char *ref_name;
void *GIT_UNUSED(_unused);
if ((error = packed_load(repo)) < GIT_SUCCESS)
return git__rethrow(error, "Failed to list references");
GIT_HASHTABLE_FOREACH(repo->references.packfile, ref_name, _unused,
if ((error = callback(ref_name, payload)) < GIT_SUCCESS)
return git__throw(error,
"Failed to list references. User callback failed");
);
}
/* now list the loose references, trying not to
* duplicate the ref names already in the packed-refs file */
data.repo_path_len = strlen(repo->path_repository);
data.list_flags = list_flags;
data.repo = repo;
data.callback = callback;
data.callback_payload = payload;
if ((error = git_buf_joinpath(&refs_path,
repo->path_repository, GIT_REFS_DIR)) < GIT_SUCCESS)
return git__rethrow(error, "Failed to alloc space for references");
error = git_path_direach(&refs_path, _dirent_loose_listall, &data);
git_buf_free(&refs_path);
return error;
}
static int cb__reflist_add(const char *ref, void *data)
{
return git_vector_insert((git_vector *)data, git__strdup(ref));
}
int git_reference_listall(
git_strarray *array,
git_repository *repo,
unsigned int list_flags)
{
int error;
git_vector ref_list;
assert(array && repo);
array->strings = NULL;
array->count = 0;
if (git_vector_init(&ref_list, 8, NULL) < GIT_SUCCESS)
return GIT_ENOMEM;
error = git_reference_foreach(
repo, list_flags, &cb__reflist_add, (void *)&ref_list);
if (error < GIT_SUCCESS) {
git_vector_free(&ref_list);
return error;
}
array->strings = (char **)ref_list.contents;
array->count = ref_list.length;
return GIT_SUCCESS;
}
int git_reference_reload(git_reference *ref)
{
int error = reference_lookup(ref);
if (error < GIT_SUCCESS)
return git__rethrow(error, "Failed to reload reference");
return GIT_SUCCESS;
}
void git_repository__refcache_free(git_refcache *refs)
{
assert(refs);
if (refs->packfile) {
const void *GIT_UNUSED(_unused);
struct packref *reference;
GIT_HASHTABLE_FOREACH(refs->packfile, _unused, reference,
free(reference);
);
git_hashtable_free(refs->packfile);
}
}
static int is_valid_ref_char(char ch)
{
if ((unsigned) ch <= ' ')
return 0;
switch (ch) {
case '~':
case '^':
case ':':
case '\\':
case '?':
case '[':
case '*':
return 0;
default:
return 1;
}
}
static int normalize_name(
char *buffer_out,
size_t out_size,
const char *name,
int is_oid_ref)
{
const char *name_end, *buffer_out_start;
const char *current;
int contains_a_slash = 0;
assert(name && buffer_out);
buffer_out_start = buffer_out;
current = name;
name_end = name + strlen(name);
/* Terminating null byte */
out_size--;
/* A refname can not be empty */
if (name_end == name)
return git__throw(GIT_EINVALIDREFNAME,
"Failed to normalize name. Reference name is empty");
/* A refname can not end with a dot or a slash */
if (*(name_end - 1) == '.' || *(name_end - 1) == '/')
return git__throw(GIT_EINVALIDREFNAME,
"Failed to normalize name. Reference name ends with dot or slash");
while (current < name_end && out_size) {
if (!is_valid_ref_char(*current))
return git__throw(GIT_EINVALIDREFNAME,
"Failed to normalize name. "
"Reference name contains invalid characters");
if (buffer_out > buffer_out_start) {
char prev = *(buffer_out - 1);
/* A refname can not start with a dot nor contain a double dot */
if (*current == '.' && ((prev == '.') || (prev == '/')))
return git__throw(GIT_EINVALIDREFNAME,
"Failed to normalize name. "
"Reference name starts with a dot or contains a double dot");
/* '@{' is forbidden within a refname */
if (*current == '{' && prev == '@')
return git__throw(GIT_EINVALIDREFNAME,
"Failed to normalize name. Reference name contains '@{'");
/* Prevent multiple slashes from being added to the output */
if (*current == '/' && prev == '/') {
current++;
continue;
}
}
if (*current == '/')
contains_a_slash = 1;
*buffer_out++ = *current++;
out_size--;
}
if (!out_size)
return git__throw(GIT_EINVALIDREFNAME, "Reference name is too long");
/* Object id refname have to contain at least one slash, except
* for HEAD in a detached state or MERGE_HEAD if we're in the
* middle of a merge */
if (is_oid_ref &&
!contains_a_slash &&
strcmp(name, GIT_HEAD_FILE) != 0 &&
strcmp(name, GIT_MERGE_HEAD_FILE) != 0 &&
strcmp(name, GIT_FETCH_HEAD_FILE) != 0)
return git__throw(GIT_EINVALIDREFNAME,
"Failed to normalize name. Reference name contains no slashes");
/* A refname can not end with ".lock" */
if (!git__suffixcmp(name, GIT_FILELOCK_EXTENSION))
return git__throw(GIT_EINVALIDREFNAME,
"Failed to normalize name. Reference name ends with '.lock'");
*buffer_out = '\0';
/*
* For object id references, name has to start with refs/. Again,
* we need to allow HEAD to be in a detached state.
*/
if (is_oid_ref && !(git__prefixcmp(buffer_out_start, GIT_REFS_DIR) ||
strcmp(buffer_out_start, GIT_HEAD_FILE)))
return git__throw(GIT_EINVALIDREFNAME,
"Failed to normalize name. "
"Reference name does not start with 'refs/'");
return GIT_SUCCESS;
}
int git_reference__normalize_name(
char *buffer_out,
size_t out_size,
const char *name)
{
return normalize_name(buffer_out, out_size, name, 0);
}
int git_reference__normalize_name_oid(
char *buffer_out,
size_t out_size,
const char *name)
{
return normalize_name(buffer_out, out_size, name, 1);
}