void test_object_raw_hash__hash_buffer_in_single_call(void)
{
git_oid id1, id2;
cl_git_pass(git_oid_fromstr(&id1, hello_id));
git_hash_buf(&id2, hello_text, strlen(hello_text));
cl_assert(git_oid_cmp(&id1, &id2) == 0);
}
int git_index__parse(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_EOBJCORRUPTED; \
buffer += _increase; \
buffer_size -= _increase;\
}
if (buffer_size < INDEX_HEADER_SIZE + INDEX_FOOTER_SIZE)
return GIT_EOBJCORRUPTED;
/* Precalculate the SHA1 of the files's contents -- we'll match it to
* the provided SHA1 in the footer */
git_hash_buf(&checksum_calculated, (const void *)buffer, buffer_size - INDEX_FOOTER_SIZE);
/* Parse header */
if (read_header(&header, buffer) < 0)
return GIT_EOBJCORRUPTED;
seek_forward(INDEX_HEADER_SIZE);
index->entry_count = header.entry_count;
/* If there is already a entires array, reuse it if it can hold all the
* entries. If not, free and reallocate */
if (index->entry_count > index->entries_size) {
free(index->entries);
index->entries_size = (uint32_t)(index->entry_count * 1.3f);
index->entries = git__malloc(index->entries_size * sizeof(git_index_entry));
}
/* Parse all the entries */
for (i = 0; i < index->entry_count && buffer_size > INDEX_FOOTER_SIZE; ++i) {
size_t entry_size;
entry_size = read_entry(&index->entries[i], buffer, buffer_size);
/* 0 bytes read means an object corruption */
if (entry_size == 0)
return GIT_EOBJCORRUPTED;
seek_forward(entry_size);
}
if (i != index->entry_count)
return GIT_EOBJCORRUPTED;
/* 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_EOBJCORRUPTED;
seek_forward(extension_size);
}
if (buffer_size != INDEX_FOOTER_SIZE)
return GIT_EOBJCORRUPTED;
/* 160-bit SHA-1 over the content of the index file before this checksum. */
git_oid_mkraw(&checksum_expected, (const unsigned char *)buffer);
if (git_oid_cmp(&checksum_calculated, &checksum_expected) != 0)
return GIT_EOBJCORRUPTED;
#undef seek_forward
return 0;
}
int git_futils_readbuffer_updated(
git_buf *out, const char *path, git_oid *checksum, int *updated)
{
int error;
git_file fd;
struct stat st;
git_buf buf = GIT_BUF_INIT;
git_oid checksum_new;
assert(out && path && *path);
if (updated != NULL)
*updated = 0;
if (p_stat(path, &st) < 0)
return git_path_set_error(errno, path, "stat");
if (S_ISDIR(st.st_mode)) {
giterr_set(GITERR_INVALID, "requested file is a directory");
return GIT_ENOTFOUND;
}
if (!git__is_sizet(st.st_size+1)) {
giterr_set(GITERR_OS, "invalid regular file stat for '%s'", path);
return -1;
}
if ((fd = git_futils_open_ro(path)) < 0)
return fd;
if (git_futils_readbuffer_fd(&buf, fd, (size_t)st.st_size) < 0) {
p_close(fd);
return -1;
}
p_close(fd);
if (checksum) {
if ((error = git_hash_buf(&checksum_new, buf.ptr, buf.size)) < 0) {
git_buf_free(&buf);
return error;
}
/*
* If we were given a checksum, we only want to use it if it's different
*/
if (!git_oid__cmp(checksum, &checksum_new)) {
git_buf_free(&buf);
if (updated)
*updated = 0;
return 0;
}
git_oid_cpy(checksum, &checksum_new);
}
/*
* If we're here, the file did change, or the user didn't have an old version
*/
if (updated != NULL)
*updated = 1;
git_buf_swap(out, &buf);
git_buf_free(&buf);
return 0;
}
void test_object_raw_short__oid_shortener_stresstest_git_oid_shorten(void)
{
#define MAX_OIDS 1000
git_oid_shorten *os;
char *oids[MAX_OIDS];
char number_buffer[16];
git_oid oid;
size_t i, j;
int min_len = 0, found_collision;
os = git_oid_shorten_new(0);
cl_assert(os != NULL);
/*
* Insert in the shortener 1000 unique SHA1 ids
*/
for (i = 0; i < MAX_OIDS; ++i) {
char *oid_text;
sprintf(number_buffer, "%u", (unsigned int)i);
git_hash_buf(&oid, number_buffer, strlen(number_buffer));
oid_text = git__malloc(GIT_OID_HEXSZ + 1);
git_oid_fmt(oid_text, &oid);
oid_text[GIT_OID_HEXSZ] = 0;
min_len = git_oid_shorten_add(os, oid_text);
cl_assert(min_len >= 0);
oids[i] = oid_text;
}
/*
* Compare the first `min_char - 1` characters of each
* SHA1 OID. If the minimizer worked, we should find at
* least one collision
*/
found_collision = 0;
for (i = 0; i < MAX_OIDS; ++i) {
for (j = 0; j < MAX_OIDS; ++j) {
if (i != j && memcmp(oids[i], oids[j], min_len - 1) == 0)
found_collision = 1;
}
}
cl_assert(found_collision == 1);
/*
* Compare the first `min_char` characters of each
* SHA1 OID. If the minimizer worked, every single preffix
* should be unique.
*/
found_collision = 0;
for (i = 0; i < MAX_OIDS; ++i) {
for (j = 0; j < MAX_OIDS; ++j) {
if (i != j && memcmp(oids[i], oids[j], min_len) == 0)
found_collision = 1;
}
}
cl_assert(found_collision == 0);
/* cleanup */
for (i = 0; i < MAX_OIDS; ++i)
git__free(oids[i]);
git_oid_shorten_free(os);
#undef MAX_OIDS
}
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;
}
