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1 #include "cache.h"
2 #include "pkt-line.h"
3 #include "run-command.h"
4
5 char packet_buffer[LARGE_PACKET_MAX];
6 static const char *packet_trace_prefix = "git";
7 static struct trace_key trace_packet = TRACE_KEY_INIT(PACKET);
8 static struct trace_key trace_pack = TRACE_KEY_INIT(PACKFILE);
9
10 void packet_trace_identity(const char *prog)
11 {
12 packet_trace_prefix = xstrdup(prog);
13 }
14
15 static const char *get_trace_prefix(void)
16 {
17 return in_async() ? "sideband" : packet_trace_prefix;
18 }
19
20 static int packet_trace_pack(const char *buf, unsigned int len, int sideband)
21 {
22 if (!sideband) {
23 trace_verbatim(&trace_pack, buf, len);
24 return 1;
25 } else if (len && *buf == '\1') {
26 trace_verbatim(&trace_pack, buf + 1, len - 1);
27 return 1;
28 } else {
29 /* it's another non-pack sideband */
30 return 0;
31 }
32 }
33
34 static void packet_trace(const char *buf, unsigned int len, int write)
35 {
36 int i;
37 struct strbuf out;
38 static int in_pack, sideband;
39
40 if (!trace_want(&trace_packet) && !trace_want(&trace_pack))
41 return;
42
43 if (in_pack) {
44 if (packet_trace_pack(buf, len, sideband))
45 return;
46 } else if (starts_with(buf, "PACK") || starts_with(buf, "\1PACK")) {
47 in_pack = 1;
48 sideband = *buf == '\1';
49 packet_trace_pack(buf, len, sideband);
50
51 /*
52 * Make a note in the human-readable trace that the pack data
53 * started.
54 */
55 buf = "PACK ...";
56 len = strlen(buf);
57 }
58
59 if (!trace_want(&trace_packet))
60 return;
61
62 /* +32 is just a guess for header + quoting */
63 strbuf_init(&out, len+32);
64
65 strbuf_addf(&out, "packet: %12s%c ",
66 get_trace_prefix(), write ? '>' : '<');
67
68 /* XXX we should really handle printable utf8 */
69 for (i = 0; i < len; i++) {
70 /* suppress newlines */
71 if (buf[i] == '\n')
72 continue;
73 if (buf[i] >= 0x20 && buf[i] <= 0x7e)
74 strbuf_addch(&out, buf[i]);
75 else
76 strbuf_addf(&out, "\\%o", buf[i]);
77 }
78
79 strbuf_addch(&out, '\n');
80 trace_strbuf(&trace_packet, &out);
81 strbuf_release(&out);
82 }
83
84 /*
85 * If we buffered things up above (we don't, but we should),
86 * we'd flush it here
87 */
88 void packet_flush(int fd)
89 {
90 packet_trace("0000", 4, 1);
91 write_or_die(fd, "0000", 4);
92 }
93
94 void packet_delim(int fd)
95 {
96 packet_trace("0001", 4, 1);
97 write_or_die(fd, "0001", 4);
98 }
99
100 int packet_flush_gently(int fd)
101 {
102 packet_trace("0000", 4, 1);
103 if (write_in_full(fd, "0000", 4) < 0)
104 return error(_("flush packet write failed"));
105 return 0;
106 }
107
108 void packet_buf_flush(struct strbuf *buf)
109 {
110 packet_trace("0000", 4, 1);
111 strbuf_add(buf, "0000", 4);
112 }
113
114 void packet_buf_delim(struct strbuf *buf)
115 {
116 packet_trace("0001", 4, 1);
117 strbuf_add(buf, "0001", 4);
118 }
119
120 static void set_packet_header(char *buf, const int size)
121 {
122 static char hexchar[] = "0123456789abcdef";
123
124 #define hex(a) (hexchar[(a) & 15])
125 buf[0] = hex(size >> 12);
126 buf[1] = hex(size >> 8);
127 buf[2] = hex(size >> 4);
128 buf[3] = hex(size);
129 #undef hex
130 }
131
132 static void format_packet(struct strbuf *out, const char *fmt, va_list args)
133 {
134 size_t orig_len, n;
135
136 orig_len = out->len;
137 strbuf_addstr(out, "0000");
138 strbuf_vaddf(out, fmt, args);
139 n = out->len - orig_len;
140
141 if (n > LARGE_PACKET_MAX)
142 die(_("protocol error: impossibly long line"));
143
144 set_packet_header(&out->buf[orig_len], n);
145 packet_trace(out->buf + orig_len + 4, n - 4, 1);
146 }
147
148 static int packet_write_fmt_1(int fd, int gently,
149 const char *fmt, va_list args)
150 {
151 static struct strbuf buf = STRBUF_INIT;
152
153 strbuf_reset(&buf);
154 format_packet(&buf, fmt, args);
155 if (write_in_full(fd, buf.buf, buf.len) < 0) {
156 if (!gently) {
157 check_pipe(errno);
158 die_errno(_("packet write with format failed"));
159 }
160 return error(_("packet write with format failed"));
161 }
162
163 return 0;
164 }
165
166 void packet_write_fmt(int fd, const char *fmt, ...)
167 {
168 va_list args;
169
170 va_start(args, fmt);
171 packet_write_fmt_1(fd, 0, fmt, args);
172 va_end(args);
173 }
174
175 int packet_write_fmt_gently(int fd, const char *fmt, ...)
176 {
177 int status;
178 va_list args;
179
180 va_start(args, fmt);
181 status = packet_write_fmt_1(fd, 1, fmt, args);
182 va_end(args);
183 return status;
184 }
185
186 static int packet_write_gently(const int fd_out, const char *buf, size_t size)
187 {
188 static char packet_write_buffer[LARGE_PACKET_MAX];
189 size_t packet_size;
190
191 if (size > sizeof(packet_write_buffer) - 4)
192 return error(_("packet write failed - data exceeds max packet size"));
193
194 packet_trace(buf, size, 1);
195 packet_size = size + 4;
196 set_packet_header(packet_write_buffer, packet_size);
197 memcpy(packet_write_buffer + 4, buf, size);
198 if (write_in_full(fd_out, packet_write_buffer, packet_size) < 0)
199 return error(_("packet write failed"));
200 return 0;
201 }
202
203 void packet_write(int fd_out, const char *buf, size_t size)
204 {
205 if (packet_write_gently(fd_out, buf, size))
206 die_errno(_("packet write failed"));
207 }
208
209 void packet_buf_write(struct strbuf *buf, const char *fmt, ...)
210 {
211 va_list args;
212
213 va_start(args, fmt);
214 format_packet(buf, fmt, args);
215 va_end(args);
216 }
217
218 void packet_buf_write_len(struct strbuf *buf, const char *data, size_t len)
219 {
220 size_t orig_len, n;
221
222 orig_len = buf->len;
223 strbuf_addstr(buf, "0000");
224 strbuf_add(buf, data, len);
225 n = buf->len - orig_len;
226
227 if (n > LARGE_PACKET_MAX)
228 die(_("protocol error: impossibly long line"));
229
230 set_packet_header(&buf->buf[orig_len], n);
231 packet_trace(data, len, 1);
232 }
233
234 int write_packetized_from_fd(int fd_in, int fd_out)
235 {
236 static char buf[LARGE_PACKET_DATA_MAX];
237 int err = 0;
238 ssize_t bytes_to_write;
239
240 while (!err) {
241 bytes_to_write = xread(fd_in, buf, sizeof(buf));
242 if (bytes_to_write < 0)
243 return COPY_READ_ERROR;
244 if (bytes_to_write == 0)
245 break;
246 err = packet_write_gently(fd_out, buf, bytes_to_write);
247 }
248 if (!err)
249 err = packet_flush_gently(fd_out);
250 return err;
251 }
252
253 int write_packetized_from_buf(const char *src_in, size_t len, int fd_out)
254 {
255 int err = 0;
256 size_t bytes_written = 0;
257 size_t bytes_to_write;
258
259 while (!err) {
260 if ((len - bytes_written) > LARGE_PACKET_DATA_MAX)
261 bytes_to_write = LARGE_PACKET_DATA_MAX;
262 else
263 bytes_to_write = len - bytes_written;
264 if (bytes_to_write == 0)
265 break;
266 err = packet_write_gently(fd_out, src_in + bytes_written, bytes_to_write);
267 bytes_written += bytes_to_write;
268 }
269 if (!err)
270 err = packet_flush_gently(fd_out);
271 return err;
272 }
273
274 static int get_packet_data(int fd, char **src_buf, size_t *src_size,
275 void *dst, unsigned size, int options)
276 {
277 ssize_t ret;
278
279 if (fd >= 0 && src_buf && *src_buf)
280 BUG("multiple sources given to packet_read");
281
282 /* Read up to "size" bytes from our source, whatever it is. */
283 if (src_buf && *src_buf) {
284 ret = size < *src_size ? size : *src_size;
285 memcpy(dst, *src_buf, ret);
286 *src_buf += ret;
287 *src_size -= ret;
288 } else {
289 ret = read_in_full(fd, dst, size);
290 if (ret < 0)
291 die_errno(_("read error"));
292 }
293
294 /* And complain if we didn't get enough bytes to satisfy the read. */
295 if (ret != size) {
296 if (options & PACKET_READ_GENTLE_ON_EOF)
297 return -1;
298
299 die(_("the remote end hung up unexpectedly"));
300 }
301
302 return ret;
303 }
304
305 static int packet_length(const char *linelen)
306 {
307 int val = hex2chr(linelen);
308 return (val < 0) ? val : (val << 8) | hex2chr(linelen + 2);
309 }
310
311 enum packet_read_status packet_read_with_status(int fd, char **src_buffer,
312 size_t *src_len, char *buffer,
313 unsigned size, int *pktlen,
314 int options)
315 {
316 int len;
317 char linelen[4];
318
319 if (get_packet_data(fd, src_buffer, src_len, linelen, 4, options) < 0) {
320 *pktlen = -1;
321 return PACKET_READ_EOF;
322 }
323
324 len = packet_length(linelen);
325
326 if (len < 0) {
327 die(_("protocol error: bad line length character: %.4s"), linelen);
328 } else if (!len) {
329 packet_trace("0000", 4, 0);
330 *pktlen = 0;
331 return PACKET_READ_FLUSH;
332 } else if (len == 1) {
333 packet_trace("0001", 4, 0);
334 *pktlen = 0;
335 return PACKET_READ_DELIM;
336 } else if (len < 4) {
337 die(_("protocol error: bad line length %d"), len);
338 }
339
340 len -= 4;
341 if ((unsigned)len >= size)
342 die(_("protocol error: bad line length %d"), len);
343
344 if (get_packet_data(fd, src_buffer, src_len, buffer, len, options) < 0) {
345 *pktlen = -1;
346 return PACKET_READ_EOF;
347 }
348
349 if ((options & PACKET_READ_CHOMP_NEWLINE) &&
350 len && buffer[len-1] == '\n')
351 len--;
352
353 buffer[len] = 0;
354 packet_trace(buffer, len, 0);
355 *pktlen = len;
356 return PACKET_READ_NORMAL;
357 }
358
359 int packet_read(int fd, char **src_buffer, size_t *src_len,
360 char *buffer, unsigned size, int options)
361 {
362 int pktlen = -1;
363
364 packet_read_with_status(fd, src_buffer, src_len, buffer, size,
365 &pktlen, options);
366
367 return pktlen;
368 }
369
370 static char *packet_read_line_generic(int fd,
371 char **src, size_t *src_len,
372 int *dst_len)
373 {
374 int len = packet_read(fd, src, src_len,
375 packet_buffer, sizeof(packet_buffer),
376 PACKET_READ_CHOMP_NEWLINE);
377 if (dst_len)
378 *dst_len = len;
379 return (len > 0) ? packet_buffer : NULL;
380 }
381
382 char *packet_read_line(int fd, int *len_p)
383 {
384 return packet_read_line_generic(fd, NULL, NULL, len_p);
385 }
386
387 int packet_read_line_gently(int fd, int *dst_len, char **dst_line)
388 {
389 int len = packet_read(fd, NULL, NULL,
390 packet_buffer, sizeof(packet_buffer),
391 PACKET_READ_CHOMP_NEWLINE|PACKET_READ_GENTLE_ON_EOF);
392 if (dst_len)
393 *dst_len = len;
394 if (dst_line)
395 *dst_line = (len > 0) ? packet_buffer : NULL;
396 return len;
397 }
398
399 char *packet_read_line_buf(char **src, size_t *src_len, int *dst_len)
400 {
401 return packet_read_line_generic(-1, src, src_len, dst_len);
402 }
403
404 ssize_t read_packetized_to_strbuf(int fd_in, struct strbuf *sb_out)
405 {
406 int packet_len;
407
408 size_t orig_len = sb_out->len;
409 size_t orig_alloc = sb_out->alloc;
410
411 for (;;) {
412 strbuf_grow(sb_out, LARGE_PACKET_DATA_MAX);
413 packet_len = packet_read(fd_in, NULL, NULL,
414 /* strbuf_grow() above always allocates one extra byte to
415 * store a '\0' at the end of the string. packet_read()
416 * writes a '\0' extra byte at the end, too. Let it know
417 * that there is already room for the extra byte.
418 */
419 sb_out->buf + sb_out->len, LARGE_PACKET_DATA_MAX+1,
420 PACKET_READ_GENTLE_ON_EOF);
421 if (packet_len <= 0)
422 break;
423 sb_out->len += packet_len;
424 }
425
426 if (packet_len < 0) {
427 if (orig_alloc == 0)
428 strbuf_release(sb_out);
429 else
430 strbuf_setlen(sb_out, orig_len);
431 return packet_len;
432 }
433 return sb_out->len - orig_len;
434 }
435
436 /* Packet Reader Functions */
437 void packet_reader_init(struct packet_reader *reader, int fd,
438 char *src_buffer, size_t src_len,
439 int options)
440 {
441 memset(reader, 0, sizeof(*reader));
442
443 reader->fd = fd;
444 reader->src_buffer = src_buffer;
445 reader->src_len = src_len;
446 reader->buffer = packet_buffer;
447 reader->buffer_size = sizeof(packet_buffer);
448 reader->options = options;
449 }
450
451 enum packet_read_status packet_reader_read(struct packet_reader *reader)
452 {
453 if (reader->line_peeked) {
454 reader->line_peeked = 0;
455 return reader->status;
456 }
457
458 reader->status = packet_read_with_status(reader->fd,
459 &reader->src_buffer,
460 &reader->src_len,
461 reader->buffer,
462 reader->buffer_size,
463 &reader->pktlen,
464 reader->options);
465
466 if (reader->status == PACKET_READ_NORMAL)
467 reader->line = reader->buffer;
468 else
469 reader->line = NULL;
470
471 return reader->status;
472 }
473
474 enum packet_read_status packet_reader_peek(struct packet_reader *reader)
475 {
476 /* Only allow peeking a single line */
477 if (reader->line_peeked)
478 return reader->status;
479
480 /* Peek a line by reading it and setting peeked flag */
481 packet_reader_read(reader);
482 reader->line_peeked = 1;
483 return reader->status;
484 }