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/*
* This file is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License, version 2,
* as published by the Free Software Foundation.
*
* In addition to the permissions in the GNU General Public License,
* the authors give you unlimited permission to link the compiled
* version of this file into combinations with other programs,
* and to distribute those combinations without any restriction
* coming from the use of this file. (The General Public License
* restrictions do apply in other respects; for example, they cover
* modification of the file, and distribution when not linked into
* a combined executable.)
*
* This file is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; see the file COPYING. If not, write to
* the Free Software Foundation, 51 Franklin Street, Fifth Floor,
* Boston, MA 02110-1301, USA.
*/
#include <stddef.h>
#include "common.h"
#include "repository.h"
#include "index.h"
#include "hash.h"
#include "git2/odb.h"
#include "git2/blob.h"
#define entry_size(type,len) ((offsetof(type, path) + (len) + 8) & ~7)
#define short_entry_size(len) entry_size(struct entry_short, len)
#define long_entry_size(len) entry_size(struct entry_long, len)
#define minimal_entry_size (offsetof(struct entry_short, path))
static const size_t INDEX_FOOTER_SIZE = GIT_OID_RAWSZ;
static const size_t INDEX_HEADER_SIZE = 12;
static const unsigned int INDEX_VERSION_NUMBER = 2;
static const unsigned int INDEX_VERSION_NUMBER_EXT = 3;
static const unsigned int INDEX_HEADER_SIG = 0x44495243;
static const char INDEX_EXT_TREECACHE_SIG[] = {'T', 'R', 'E', 'E'};
static const char INDEX_EXT_UNMERGED_SIG[] = {'R', 'E', 'U', 'C'};
struct index_header {
uint32_t signature;
uint32_t version;
uint32_t entry_count;
};
struct index_extension {
char signature[4];
uint32_t extension_size;
};
struct entry_time {
uint32_t seconds;
uint32_t nanoseconds;
};
struct entry_short {
struct entry_time ctime;
struct entry_time mtime;
uint32_t dev;
uint32_t ino;
uint32_t mode;
uint32_t uid;
uint32_t gid;
uint32_t file_size;
git_oid oid;
uint16_t flags;
char path[1]; /* arbitrary length */
};
struct entry_long {
struct entry_time ctime;
struct entry_time mtime;
uint32_t dev;
uint32_t ino;
uint32_t mode;
uint32_t uid;
uint32_t gid;
uint32_t file_size;
git_oid oid;
uint16_t flags;
uint16_t flags_extended;
char path[1]; /* arbitrary length */
};
/* local declarations */
static size_t read_extension(git_index *index, const char *buffer, size_t buffer_size);
static size_t read_entry(git_index_entry *dest, const void *buffer, size_t buffer_size);
static int read_header(struct index_header *dest, const void *buffer);
static int read_tree(git_index *index, const char *buffer, size_t buffer_size);
static int read_tree_internal(git_index_tree **, const char **, const char *, git_index_tree *);
static int parse_index(git_index *index, const char *buffer, size_t buffer_size);
static int is_index_extended(git_index *index);
static int write_index(git_index *index, git_filebuf *file);
static int index_srch(const void *key, const void *array_member)
{
const git_index_entry *entry = array_member;
return strcmp(key, entry->path);
}
static int index_cmp(const void *a, const void *b)
{
const git_index_entry *entry_a = a;
const git_index_entry *entry_b = b;
return strcmp(entry_a->path, entry_b->path);
}
static int unmerged_srch(const void *key, const void *array_member)
{
const git_index_entry_unmerged *entry = array_member;
return strcmp(key, entry->path);
}
static int unmerged_cmp(const void *a, const void *b)
{
const git_index_entry_unmerged *info_a = a;
const git_index_entry_unmerged *info_b = b;
return strcmp(info_a->path, info_b->path);
}
static unsigned int index_create_mode(unsigned int mode)
{
if (S_ISLNK(mode))
return S_IFLNK;
if (S_ISDIR(mode) || (mode & S_IFMT) == (S_IFLNK | S_IFDIR))
return (S_IFLNK | S_IFDIR);
return S_IFREG | ((mode & 0100) ? 0755 : 0644);
}
static int index_initialize(git_index **index_out, git_repository *owner, const char *index_path)
{
git_index *index;
assert(index_out && index_path);
index = git__malloc(sizeof(git_index));
if (index == NULL)
return GIT_ENOMEM;
memset(index, 0x0, sizeof(git_index));
index->index_file_path = git__strdup(index_path);
if (index->index_file_path == NULL) {
free(index);
return GIT_ENOMEM;
}
index->repository = owner;
git_vector_init(&index->entries, 32, index_cmp);
/* Check if index file is stored on disk already */
if (git_futils_exists(index->index_file_path) == 0)
index->on_disk = 1;
*index_out = index;
return git_index_read(index);
}
int git_index_open(git_index **index_out, const char *index_path)
{
return index_initialize(index_out, NULL, index_path);
}
/*
* Moved from `repository.c`
*/
int git_repository_index(git_index **index_out, git_repository *repo)
{
if (repo->is_bare)
return git__throw(GIT_EBAREINDEX, "Failed to open index. Repository is bare");
return index_initialize(index_out, repo, repo->path_index);
}
void git_index_free(git_index *index)
{
if (index == NULL)
return;
git_index_clear(index);
free(index->index_file_path);
free(index);
}
static void free_tree(git_index_tree *tree)
{
unsigned int i;
if (tree == NULL)
return;
for (i = 0; i < tree->children_count; ++i)
free_tree(tree->children[i]);
free(tree->name);
free(tree->children);
free(tree);
}
void git_index_clear(git_index *index)
{
unsigned int i;
assert(index);
for (i = 0; i < index->entries.length; ++i) {
git_index_entry *e;
e = git_vector_get(&index->entries, i);
free((char *)e->path);
free(e);
}
for (i = 0; i < index->unmerged.length; ++i) {
git_index_entry_unmerged *e;
e = git_vector_get(&index->unmerged, i);
free((char *)e->path);
free(e);
}
git_vector_clear(&index->entries);
git_vector_clear(&index->unmerged);
index->last_modified = 0;
free_tree(index->tree);
index->tree = NULL;
}
int git_index_read(git_index *index)
{
struct stat indexst;
int error = GIT_SUCCESS;
assert(index->index_file_path);
if (!index->on_disk || git_futils_exists(index->index_file_path) < 0) {
git_index_clear(index);
index->on_disk = 0;
return GIT_SUCCESS;
}
if (p_stat(index->index_file_path, &indexst) < 0)
return git__throw(GIT_EOSERR, "Failed to read index. %s does not exist or is corrupted", index->index_file_path);
if (!S_ISREG(indexst.st_mode))
return git__throw(GIT_ENOTFOUND, "Failed to read index. %s is not an index file", index->index_file_path);
if (indexst.st_mtime != index->last_modified) {
git_fbuffer buffer;
if ((error = git_futils_readbuffer(&buffer, index->index_file_path)) < GIT_SUCCESS)
return git__rethrow(error, "Failed to read index");
git_index_clear(index);
error = parse_index(index, buffer.data, buffer.len);
if (error == GIT_SUCCESS)
index->last_modified = indexst.st_mtime;
git_futils_freebuffer(&buffer);
}
if (error < GIT_SUCCESS)
return git__rethrow(error, "Failed to read index");
return error;
}
int git_index_write(git_index *index)
{
git_filebuf file;
struct stat indexst;
int error;
git_vector_sort(&index->entries);
if ((error = git_filebuf_open(&file, index->index_file_path, GIT_FILEBUF_HASH_CONTENTS)) < GIT_SUCCESS)
return git__rethrow(error, "Failed to write index");
if ((error = write_index(index, &file)) < GIT_SUCCESS) {
git_filebuf_cleanup(&file);
return git__rethrow(error, "Failed to write index");
}
if ((error = git_filebuf_commit(&file)) < GIT_SUCCESS)
return git__rethrow(error, "Failed to write index");
if (p_stat(index->index_file_path, &indexst) == 0) {
index->last_modified = indexst.st_mtime;
index->on_disk = 1;
}
return GIT_SUCCESS;
}
unsigned int git_index_entrycount(git_index *index)
{
assert(index);
return index->entries.length;
}
unsigned int git_index_entrycount_unmerged(git_index *index)
{
assert(index);
return index->unmerged.length;
}
git_index_entry *git_index_get(git_index *index, unsigned int n)
{
git_vector_sort(&index->entries);
return git_vector_get(&index->entries, n);
}
static int index_insert(git_index *index, const git_index_entry *source_entry, int replace)
{
git_index_entry *entry;
size_t path_length;
int position;
git_index_entry **entry_array;
assert(index && source_entry);
if (source_entry->path == NULL)
return git__throw(GIT_EMISSINGOBJDATA, "Failed to insert into index. Entry has no path");
entry = git__malloc(sizeof(git_index_entry));
if (entry == NULL)
return GIT_ENOMEM;
memcpy(entry, source_entry, sizeof(git_index_entry));
/* duplicate the path string so we own it */
entry->path = git__strdup(entry->path);
if (entry->path == NULL)
return GIT_ENOMEM;
/* make sure that the path length flag is correct */
path_length = strlen(entry->path);
entry->flags &= ~GIT_IDXENTRY_NAMEMASK;
if (path_length < GIT_IDXENTRY_NAMEMASK)
entry->flags |= path_length & GIT_IDXENTRY_NAMEMASK;
else
entry->flags |= GIT_IDXENTRY_NAMEMASK;;
/*
* replacing is not requested: just insert entry at the end;
* the index is no longer sorted
*/
if (!replace) {
if (git_vector_insert(&index->entries, entry) < GIT_SUCCESS)
goto cleanup_oom;
return GIT_SUCCESS;
}
/* look if an entry with this path already exists */
position = git_index_find(index, source_entry->path);
/*
* if no entry exists add the entry at the end;
* the index is no longer sorted
*/
if (position == GIT_ENOTFOUND) {
if (git_vector_insert(&index->entries, entry) < GIT_SUCCESS)
goto cleanup_oom;
return GIT_SUCCESS;
}
/* exists, replace it */
entry_array = (git_index_entry **) index->entries.contents;
free((char *)entry_array[position]->path);
free(entry_array[position]);
entry_array[position] = entry;
return GIT_SUCCESS;
cleanup_oom:
free((char *)entry->path);
free(entry);
return GIT_ENOMEM;;
}
static int index_init_entry(git_index_entry *entry, git_index *index, const char *rel_path, int stage)
{
char full_path[GIT_PATH_MAX];
struct stat st;
int error;
if (index->repository == NULL)
return git__throw(GIT_EBAREINDEX, "Failed to initialize entry. Repository is bare");
git_path_join(full_path, index->repository->path_workdir, rel_path);
if (p_lstat(full_path, &st) < 0)
return git__throw(GIT_ENOTFOUND, "Failed to initialize entry. '%s' cannot be opened", full_path);
if (stage < 0 || stage > 3)
return git__throw(GIT_ERROR, "Failed to initialize entry. Invalid stage %i", stage);
memset(entry, 0x0, sizeof(git_index_entry));
entry->ctime.seconds = (git_time_t)st.st_ctime;
entry->mtime.seconds = (git_time_t)st.st_mtime;
/* entry.mtime.nanoseconds = st.st_mtimensec; */
/* entry.ctime.nanoseconds = st.st_ctimensec; */
entry->dev= st.st_rdev;
entry->ino = st.st_ino;
entry->mode = index_create_mode(st.st_mode);
entry->uid = st.st_uid;
entry->gid = st.st_gid;
entry->file_size = st.st_size;
/* write the blob to disk and get the oid */
if ((error = git_blob_create_fromfile(&entry->oid, index->repository, rel_path)) < GIT_SUCCESS)
return git__rethrow(error, "Failed to initialize index entry");
entry->flags |= (stage << GIT_IDXENTRY_STAGESHIFT);
entry->path = rel_path; /* do not duplicate; index_insert already does this */
return GIT_SUCCESS;
}
int git_index_add(git_index *index, const char *path, int stage)
{
int error;
git_index_entry entry;
if ((error = index_init_entry(&entry, index, path, stage)) < GIT_SUCCESS)
return git__rethrow(error, "Failed to add to index");
return index_insert(index, &entry, 1);
}
int git_index_append(git_index *index, const char *path, int stage)
{
int error;
git_index_entry entry;
if ((error = index_init_entry(&entry, index, path, stage)) < GIT_SUCCESS)
return git__rethrow(error, "Failed to append to index");
return index_insert(index, &entry, 0);
}
int git_index_add2(git_index *index, const git_index_entry *source_entry)
{
return index_insert(index, source_entry, 1);
}
int git_index_append2(git_index *index, const git_index_entry *source_entry)
{
return index_insert(index, source_entry, 0);
}
int git_index_remove(git_index *index, int position)
{
git_vector_sort(&index->entries);
return git_vector_remove(&index->entries, (unsigned int)position);
}
int git_index_find(git_index *index, const char *path)
{
return git_vector_bsearch2(&index->entries, index_srch, path);
}
void git_index_uniq(git_index *index)
{
git_vector_uniq(&index->entries);
}
const git_index_entry_unmerged *git_index_get_unmerged_bypath(git_index *index, const char *path)
{
int pos;
assert(index && path);
if (!index->unmerged.length)
return NULL;
if ((pos = git_vector_bsearch2(&index->unmerged, unmerged_srch, path)) < GIT_SUCCESS)
return NULL;
return git_vector_get(&index->unmerged, pos);
}
const git_index_entry_unmerged *git_index_get_unmerged_byindex(git_index *index, unsigned int n)
{
assert(index);
return git_vector_get(&index->unmerged, n);
}
static int read_tree_internal(git_index_tree **out,
const char **buffer_in, const char *buffer_end, git_index_tree *parent)
{
git_index_tree *tree;
const char *name_start, *buffer;
long count;
int error = GIT_SUCCESS;
if ((tree = git__malloc(sizeof(git_index_tree))) == NULL)
return GIT_ENOMEM;
memset(tree, 0x0, sizeof(git_index_tree));
tree->parent = parent;
buffer = name_start = *buffer_in;
if ((buffer = memchr(buffer, '\0', buffer_end - buffer)) == NULL) {
error = GIT_EOBJCORRUPTED;
goto cleanup;
}
/* NUL-terminated tree name */
tree->name = git__strdup(name_start);
if (tree->name == NULL) {
error = GIT_ENOMEM;
goto cleanup;
}
if (++buffer >= buffer_end) {
error = GIT_EOBJCORRUPTED;
goto cleanup;
}
/* Blank-terminated ASCII decimal number of entries in this tree */
if (git__strtol32(&count, buffer, &buffer, 10) < GIT_SUCCESS || count < -1) {
error = GIT_EOBJCORRUPTED;
goto cleanup;
}
/* Invalidated TREE. Free the tree but report success */
if (count == -1) {
/* FIXME: return buffer_end or the end position for
* this single tree entry */
*buffer_in = buffer_end;
*out = NULL;
free_tree(tree); /* Needs to be done manually */
return GIT_SUCCESS;
}
tree->entries = count;
if (*buffer != ' ' || ++buffer >= buffer_end) {
error = GIT_EOBJCORRUPTED;
goto cleanup;
}
/* Number of children of the tree, newline-terminated */
if (git__strtol32(&count, buffer, &buffer, 10) < GIT_SUCCESS ||
count < 0) {
error = GIT_EOBJCORRUPTED;
goto cleanup;
}
tree->children_count = count;
if (*buffer != '\n' || ++buffer >= buffer_end) {
error = GIT_EOBJCORRUPTED;
goto cleanup;
}
/* 160-bit SHA-1 for this tree and it's children */
if (buffer + GIT_OID_RAWSZ > buffer_end) {
error = GIT_EOBJCORRUPTED;
goto cleanup;
}
git_oid_fromraw(&tree->oid, (const unsigned char *)buffer);
buffer += GIT_OID_RAWSZ;
/* Parse children: */
if (tree->children_count > 0) {
unsigned int i;
int err;
tree->children = git__malloc(tree->children_count * sizeof(git_index_tree *));
if (tree->children == NULL)
goto cleanup;
for (i = 0; i < tree->children_count; ++i) {
err = read_tree_internal(&tree->children[i], &buffer, buffer_end, tree);
if (err < GIT_SUCCESS)
goto cleanup;
}
}
*buffer_in = buffer;
*out = tree;
return GIT_SUCCESS;
cleanup:
free_tree(tree);
return error;
}
static int read_tree(git_index *index, const char *buffer, size_t buffer_size)
{
const char *buffer_end = buffer + buffer_size;
int error;
error = read_tree_internal(&index->tree, &buffer, buffer_end, NULL);
if (buffer < buffer_end)
return GIT_EOBJCORRUPTED;
return error;
}
static int read_unmerged(git_index *index, const char *buffer, size_t size)
{
const char *endptr;
size_t len;
int i;
git_vector_init(&index->unmerged, 16, unmerged_cmp);
while (size) {
git_index_entry_unmerged *lost;
len = strlen(buffer) + 1;
if (size <= len)
return git__throw(GIT_ERROR, "Failed to read unmerged entries");
if ((lost = git__malloc(sizeof(git_index_entry_unmerged))) == NULL)
return GIT_ENOMEM;
if (git_vector_insert(&index->unmerged, lost) < GIT_SUCCESS)
return git__throw(GIT_ERROR, "Failed to read unmerged entries");
lost->path = git__strdup(buffer);
if (!lost->path)
return GIT_ENOMEM;
size -= len;
buffer += len;
for (i = 0; i < 3; i++) {
long tmp;
if (git__strtol32(&tmp, buffer, &endptr, 8) < GIT_SUCCESS ||
!endptr || endptr == buffer || *endptr || tmp > UINT_MAX)
return GIT_ERROR;
lost->mode[i] = tmp;
len = (endptr + 1) - buffer;
if (size <= len)
return git__throw(GIT_ERROR, "Failed to read unmerged entries");
size -= len;
buffer += len;
}
for (i = 0; i < 3; i++) {
if (!lost->mode[i])
continue;
if (size < 20)
return git__throw(GIT_ERROR, "Failed to read unmerged entries");
git_oid_fromraw(&lost->oid[i], (unsigned char *) buffer);
size -= 20;
buffer += 20;
}
}
return GIT_SUCCESS;
}
static size_t read_entry(git_index_entry *dest, const void *buffer, size_t buffer_size)
{
size_t path_length, entry_size;
uint16_t flags_raw;
const char *path_ptr;
const struct entry_short *source = buffer;
if (INDEX_FOOTER_SIZE + minimal_entry_size > buffer_size)
return 0;
memset(dest, 0x0, sizeof(git_index_entry));
dest->ctime.seconds = (git_time_t)ntohl(source->ctime.seconds);
dest->ctime.nanoseconds = ntohl(source->ctime.nanoseconds);
dest->mtime.seconds = (git_time_t)ntohl(source->mtime.seconds);
dest->mtime.nanoseconds = ntohl(source->mtime.nanoseconds);
dest->dev = ntohl(source->dev);
dest->ino = ntohl(source->ino);
dest->mode = ntohl(source->mode);
dest->uid = ntohl(source->uid);
dest->gid = ntohl(source->gid);
dest->file_size = ntohl(source->file_size);
git_oid_cpy(&dest->oid, &source->oid);
dest->flags = ntohs(source->flags);
if (dest->flags & GIT_IDXENTRY_EXTENDED) {
struct entry_long *source_l = (struct entry_long *)source;
path_ptr = source_l->path;
flags_raw = ntohs(source_l->flags_extended);
memcpy(&dest->flags_extended, &flags_raw, 2);
} else
path_ptr = source->path;
path_length = dest->flags & GIT_IDXENTRY_NAMEMASK;
/* if this is a very long string, we must find its
* real length without overflowing */
if (path_length == 0xFFF) {
const char *path_end;
path_end = memchr(path_ptr, '\0', buffer_size);
if (path_end == NULL)
return 0;
path_length = path_end - path_ptr;
}
if (dest->flags & GIT_IDXENTRY_EXTENDED)
entry_size = long_entry_size(path_length);
else
entry_size = short_entry_size(path_length);
if (INDEX_FOOTER_SIZE + entry_size > buffer_size)
return 0;
dest->path = git__strdup(path_ptr);
assert(dest->path);
return entry_size;
}
static int read_header(struct index_header *dest, const void *buffer)
{
const struct index_header *source = buffer;
dest->signature = ntohl(source->signature);
if (dest->signature != INDEX_HEADER_SIG)
return GIT_EOBJCORRUPTED;
dest->version = ntohl(source->version);
if (dest->version != INDEX_VERSION_NUMBER_EXT &&
dest->version != INDEX_VERSION_NUMBER)
return GIT_EOBJCORRUPTED;
dest->entry_count = ntohl(source->entry_count);
return GIT_SUCCESS;
}
static size_t read_extension(git_index *index, const char *buffer, size_t buffer_size)
{
const struct index_extension *source;
struct index_extension dest;
size_t total_size;
source = (const struct index_extension *)(buffer);
memcpy(dest.signature, source->signature, 4);
dest.extension_size = ntohl(source->extension_size);
total_size = dest.extension_size + sizeof(struct index_extension);
if (buffer_size - total_size < INDEX_FOOTER_SIZE)
return 0;
/* optional extension */
if (dest.signature[0] >= 'A' && dest.signature[0] <= 'Z') {
/* tree cache */
if (memcmp(dest.signature, INDEX_EXT_TREECACHE_SIG, 4) == 0) {
if (read_tree(index, buffer + 8, dest.extension_size) < GIT_SUCCESS)
return 0;
} else if (memcmp(dest.signature, INDEX_EXT_UNMERGED_SIG, 4) == 0) {
if (read_unmerged(index, buffer + 8, dest.extension_size) < GIT_SUCCESS)
return 0;
}
/* else, unsupported extension. We cannot parse this, but we can skip
* it by returning `total_size */
} else {
/* we cannot handle non-ignorable extensions;
* in fact they aren't even defined in the standard */
return 0;
}
return total_size;
}
static int parse_index(git_index *index, const char *buffer, size_t buffer_size)
{
unsigned int i;
struct index_header header;
git_oid checksum_calculated, checksum_expected;
#define seek_forward(_increase) { \
if (_increase >= buffer_size) \
return git__throw(GIT_EOBJCORRUPTED, "Failed to seek forward. Buffer size exceeded"); \
buffer += _increase; \
buffer_size -= _increase;\
}
if (buffer_size < INDEX_HEADER_SIZE + INDEX_FOOTER_SIZE)
return git__throw(GIT_EOBJCORRUPTED, "Failed to parse index. Buffer too small");
/* Precalculate the SHA1 of the files's contents -- we'll match it to
* the provided SHA1 in the footer */
git_hash_buf(&checksum_calculated, buffer, buffer_size - INDEX_FOOTER_SIZE);
/* Parse header */
if (read_header(&header, buffer) < GIT_SUCCESS)
return git__throw(GIT_EOBJCORRUPTED, "Failed to parse index. Header is corrupted");
seek_forward(INDEX_HEADER_SIZE);
git_vector_clear(&index->entries);
/* Parse all the entries */
for (i = 0; i < header.entry_count && buffer_size > INDEX_FOOTER_SIZE; ++i) {
size_t entry_size;
git_index_entry *entry;
entry = git__malloc(sizeof(git_index_entry));
if (entry == NULL)
return GIT_ENOMEM;
entry_size = read_entry(entry, buffer, buffer_size);
/* 0 bytes read means an object corruption */
if (entry_size == 0)
return git__throw(GIT_EOBJCORRUPTED, "Failed to parse index. Entry size is zero");
if (git_vector_insert(&index->entries, entry) < GIT_SUCCESS)
return GIT_ENOMEM;
seek_forward(entry_size);
}
if (i != header.entry_count)
return git__throw(GIT_EOBJCORRUPTED, "Failed to parse index. Header entries changed while parsing");
/* There's still space for some extensions! */
while (buffer_size > INDEX_FOOTER_SIZE) {
size_t extension_size;
extension_size = read_extension(index, buffer, buffer_size);
/* see if we have read any bytes from the extension */
if (extension_size == 0)
return git__throw(GIT_EOBJCORRUPTED, "Failed to parse index. Extension size is zero");
seek_forward(extension_size);
}
if (buffer_size != INDEX_FOOTER_SIZE)
return git__throw(GIT_EOBJCORRUPTED, "Failed to parse index. Buffer size does not match index footer size");
/* 160-bit SHA-1 over the content of the index file before this checksum. */
git_oid_fromraw(&checksum_expected, (const unsigned char *)buffer);
if (git_oid_cmp(&checksum_calculated, &checksum_expected) != 0)
return git__throw(GIT_EOBJCORRUPTED, "Failed to parse index. Calculated checksum does not match expected checksum");
#undef seek_forward
/* force sorting in the vector: the entries are
* assured to be sorted on the index */
index->entries.sorted = 1;
return GIT_SUCCESS;
}
static int is_index_extended(git_index *index)
{
unsigned int i, extended;
extended = 0;
for (i = 0; i < index->entries.length; ++i) {
git_index_entry *entry;
entry = git_vector_get(&index->entries, i);
entry->flags &= ~GIT_IDXENTRY_EXTENDED;
if (entry->flags_extended & GIT_IDXENTRY_EXTENDED_FLAGS) {
extended++;
entry->flags |= GIT_IDXENTRY_EXTENDED;
}
}
return extended;
}
static int write_disk_entry(git_filebuf *file, git_index_entry *entry)
{
struct entry_short *ondisk;
size_t path_len, disk_size;
char *path;
path_len = strlen(entry->path);
if (entry->flags & GIT_IDXENTRY_EXTENDED)
disk_size = long_entry_size(path_len);
else
disk_size = short_entry_size(path_len);
if (git_filebuf_reserve(file, (void **)&ondisk, disk_size) < GIT_SUCCESS)
return GIT_ENOMEM;
memset(ondisk, 0x0, disk_size);
/**
* Yes, we have to truncate.
*
* The on-disk format for Index entries clearly defines
* the time and size fields to be 4 bytes each -- so even if
* we store these values with 8 bytes on-memory, they must
* be truncated to 4 bytes before writing to disk.
*
* In 2038 I will be either too dead or too rich to care about this
*/
ondisk->ctime.seconds = htonl((uint32_t)entry->ctime.seconds);
ondisk->mtime.seconds = htonl((uint32_t)entry->mtime.seconds);
ondisk->ctime.nanoseconds = htonl(entry->ctime.nanoseconds);
ondisk->mtime.nanoseconds = htonl(entry->mtime.nanoseconds);
ondisk->dev = htonl(entry->dev);
ondisk->ino = htonl(entry->ino);
ondisk->mode = htonl(entry->mode);
ondisk->uid = htonl(entry->uid);
ondisk->gid = htonl(entry->gid);
ondisk->file_size = htonl((uint32_t)entry->file_size);
git_oid_cpy(&ondisk->oid, &entry->oid);
ondisk->flags = htons(entry->flags);
if (entry->flags & GIT_IDXENTRY_EXTENDED) {
struct entry_long *ondisk_ext;
ondisk_ext = (struct entry_long *)ondisk;
ondisk_ext->flags_extended = htons(entry->flags_extended);
path = ondisk_ext->path;
}
else
path = ondisk->path;
memcpy(path, entry->path, path_len);
return GIT_SUCCESS;
}
static int write_entries(git_index *index, git_filebuf *file)
{
unsigned int i;
for (i = 0; i < index->entries.length; ++i) {
git_index_entry *entry;
entry = git_vector_get(&index->entries, i);
if (write_disk_entry(file, entry) < GIT_SUCCESS)
return GIT_ENOMEM;
}
return GIT_SUCCESS;
}
static int write_index(git_index *index, git_filebuf *file)
{
int error = GIT_SUCCESS;
git_oid hash_final;
struct index_header header;
int is_extended;
assert(index && file);
is_extended = is_index_extended(index);
header.signature = htonl(INDEX_HEADER_SIG);
header.version = htonl(is_extended ? INDEX_VERSION_NUMBER_EXT : INDEX_VERSION_NUMBER);
header.entry_count = htonl(index->entries.length);
git_filebuf_write(file, &header, sizeof(struct index_header));
error = write_entries(index, file);
if (error < GIT_SUCCESS)
return git__rethrow(error, "Failed to write index");
/* TODO: write extensions (tree cache) */
/* get out the hash for all the contents we've appended to the file */
git_filebuf_hash(&hash_final, file);
/* write it at the end of the file */
git_filebuf_write(file, hash_final.id, GIT_OID_RAWSZ);
return error == GIT_SUCCESS ? GIT_SUCCESS : git__rethrow(error, "Failed to write index");
}
int git_index_entry_stage(const git_index_entry *entry)
{
return (entry->flags & GIT_IDXENTRY_STAGEMASK) >> GIT_IDXENTRY_STAGESHIFT;
}