/*
* Copyright (C) 2009-2012 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 "common.h"
#include "git2/types.h"
#include "git2/errors.h"
#include "git2/refs.h"
#include "git2/revwalk.h"
#include "pkt.h"
#include "util.h"
#include "netops.h"
#include "posix.h"
#include "buffer.h"
#include <ctype.h>
#define PKT_LEN_SIZE 4
static const char pkt_done_str[] = "0009done\n";
static const char pkt_flush_str[] = "0000";
static const char pkt_have_prefix[] = "0032have ";
static const char pkt_want_prefix[] = "0032want ";
static int flush_pkt(git_pkt **out)
{
git_pkt *pkt;
pkt = git__malloc(sizeof(git_pkt));
GITERR_CHECK_ALLOC(pkt);
pkt->type = GIT_PKT_FLUSH;
*out = pkt;
return 0;
}
/* the rest of the line will be useful for multi_ack */
static int ack_pkt(git_pkt **out, const char *line, size_t len)
{
git_pkt *pkt;
GIT_UNUSED(line);
GIT_UNUSED(len);
pkt = git__malloc(sizeof(git_pkt));
GITERR_CHECK_ALLOC(pkt);
pkt->type = GIT_PKT_ACK;
*out = pkt;
return 0;
}
static int nak_pkt(git_pkt **out)
{
git_pkt *pkt;
pkt = git__malloc(sizeof(git_pkt));
GITERR_CHECK_ALLOC(pkt);
pkt->type = GIT_PKT_NAK;
*out = pkt;
return 0;
}
static int pack_pkt(git_pkt **out)
{
git_pkt *pkt;
pkt = git__malloc(sizeof(git_pkt));
GITERR_CHECK_ALLOC(pkt);
pkt->type = GIT_PKT_PACK;
*out = pkt;
return 0;
}
static int comment_pkt(git_pkt **out, const char *line, size_t len)
{
git_pkt_comment *pkt;
pkt = git__malloc(sizeof(git_pkt_comment) + len + 1);
GITERR_CHECK_ALLOC(pkt);
pkt->type = GIT_PKT_COMMENT;
memcpy(pkt->comment, line, len);
pkt->comment[len] = '\0';
*out = (git_pkt *) pkt;
return 0;
}
/*
* Parse an other-ref line.
*/
static int ref_pkt(git_pkt **out, const char *line, size_t len)
{
int error;
git_pkt_ref *pkt;
pkt = git__malloc(sizeof(git_pkt_ref));
GITERR_CHECK_ALLOC(pkt);
memset(pkt, 0x0, sizeof(git_pkt_ref));
pkt->type = GIT_PKT_REF;
if ((error = git_oid_fromstr(&pkt->head.oid, line)) < 0)
goto error_out;
/* Check for a bit of consistency */
if (line[GIT_OID_HEXSZ] != ' ') {
giterr_set(GITERR_NET, "Error parsing pkt-line");
error = -1;
goto error_out;
}
/* Jump from the name */
line += GIT_OID_HEXSZ + 1;
len -= (GIT_OID_HEXSZ + 1);
if (line[len - 1] == '\n')
--len;
pkt->head.name = git__malloc(len + 1);
GITERR_CHECK_ALLOC(pkt->head.name);
memcpy(pkt->head.name, line, len);
pkt->head.name[len] = '\0';
if (strlen(pkt->head.name) < len) {
pkt->capabilities = strchr(pkt->head.name, '\0') + 1;
}
*out = (git_pkt *)pkt;
return 0;
error_out:
git__free(pkt);
return error;
}
static int32_t parse_len(const char *line)
{
char num[PKT_LEN_SIZE + 1];
int i, error;
int32_t len;
const char *num_end;
memcpy(num, line, PKT_LEN_SIZE);
num[PKT_LEN_SIZE] = '\0';
for (i = 0; i < PKT_LEN_SIZE; ++i) {
if (!isxdigit(num[i])) {
giterr_set(GITERR_NET, "Found invalid hex digit in length");
return -1;
}
}
if ((error = git__strtol32(&len, num, &num_end, 16)) < 0)
return error;
return len;
}
/*
* As per the documentation, the syntax is:
*
* pkt-line = data-pkt / flush-pkt
* data-pkt = pkt-len pkt-payload
* pkt-len = 4*(HEXDIG)
* pkt-payload = (pkt-len -4)*(OCTET)
* flush-pkt = "0000"
*
* Which means that the first four bytes are the length of the line,
* in ASCII hexadecimal (including itself)
*/
int git_pkt_parse_line(
git_pkt **head, const char *line, const char **out, size_t bufflen)
{
int ret;
int32_t len;
/* Not even enough for the length */
if (bufflen > 0 && bufflen < PKT_LEN_SIZE)
return GIT_ESHORTBUFFER;
len = parse_len(line);
if (len < 0) {
/*
* If we fail to parse the length, it might be because the
* server is trying to send us the packfile already.
*/
if (bufflen >= 4 && !git__prefixcmp(line, "PACK")) {
*out = line;
return pack_pkt(head);
}
return (int)len;
}
/*
* If we were given a buffer length, then make sure there is
* enough in the buffer to satisfy this line
*/
if (bufflen > 0 && bufflen < (size_t)len)
return GIT_ESHORTBUFFER;
line += PKT_LEN_SIZE;
/*
* TODO: How do we deal with empty lines? Try again? with the next
* line?
*/
if (len == PKT_LEN_SIZE) {
*out = line;
return 0;
}
if (len == 0) { /* Flush pkt */
*out = line;
return flush_pkt(head);
}
len -= PKT_LEN_SIZE; /* the encoded length includes its own size */
/* Assming the minimal size is actually 4 */
if (!git__prefixcmp(line, "ACK"))
ret = ack_pkt(head, line, len);
else if (!git__prefixcmp(line, "NAK"))
ret = nak_pkt(head);
else if (*line == '#')
ret = comment_pkt(head, line, len);
else
ret = ref_pkt(head, line, len);
*out = line + len;
return ret;
}
void git_pkt_free(git_pkt *pkt)
{
if (pkt->type == GIT_PKT_REF) {
git_pkt_ref *p = (git_pkt_ref *) pkt;
git__free(p->head.name);
}
git__free(pkt);
}
int git_pkt_buffer_flush(git_buf *buf)
{
return git_buf_put(buf, pkt_flush_str, strlen(pkt_flush_str));
}
int git_pkt_send_flush(GIT_SOCKET s)
{
return gitno_send(s, pkt_flush_str, strlen(pkt_flush_str), 0);
}
static int buffer_want_with_caps(git_remote_head *head, git_transport_caps *caps, git_buf *buf)
{
char capstr[20];
char oid[GIT_OID_HEXSZ +1] = {0};
unsigned int len;
if (caps->ofs_delta)
strncpy(capstr, GIT_CAP_OFS_DELTA, sizeof(capstr));
len = (unsigned int)
(strlen("XXXXwant ") + GIT_OID_HEXSZ + 1 /* NUL */ +
strlen(capstr) + 1 /* LF */);
git_buf_grow(buf, git_buf_len(buf) + len);
git_oid_fmt(oid, &head->oid);
return git_buf_printf(buf, "%04xwant %s%c%s\n", len, oid, 0, capstr);
}
/*
* All "want" packets have the same length and format, so what we do
* is overwrite the OID each time.
*/
int git_pkt_buffer_wants(const git_vector *refs, git_transport_caps *caps, git_buf *buf)
{
unsigned int i = 0;
git_remote_head *head;
if (caps->common) {
for (; i < refs->length; ++i) {
head = refs->contents[i];
if (!head->local)
break;
}
if (buffer_want_with_caps(refs->contents[i], caps, buf) < 0)
return -1;
i++;
}
for (; i < refs->length; ++i) {
char oid[GIT_OID_HEXSZ];
head = refs->contents[i];
if (head->local)
continue;
git_oid_fmt(oid, &head->oid);
git_buf_put(buf, pkt_want_prefix, strlen(pkt_want_prefix));
git_buf_put(buf, oid, GIT_OID_HEXSZ);
git_buf_putc(buf, '\n');
if (git_buf_oom(buf))
return -1;
}
return git_pkt_buffer_flush(buf);
}
int git_pkt_buffer_have(git_oid *oid, git_buf *buf)
{
char oidhex[GIT_OID_HEXSZ + 1];
memset(oidhex, 0x0, sizeof(oidhex));
git_oid_fmt(oidhex, oid);
return git_buf_printf(buf, "%s%s\n", pkt_have_prefix, oidhex);
}
int git_pkt_buffer_done(git_buf *buf)
{
return git_buf_puts(buf, pkt_done_str);
}
