diff options
Diffstat (limited to 'pkt-line.c')
| -rw-r--r-- | pkt-line.c | 244 |
1 files changed, 187 insertions, 57 deletions
diff --git a/pkt-line.c b/pkt-line.c index b4cb7e2756..08a1427c0d 100644 --- a/pkt-line.c +++ b/pkt-line.c @@ -1,36 +1,78 @@ #include "cache.h" #include "pkt-line.h" -/* - * Write a packetized stream, where each line is preceded by - * its length (including the header) as a 4-byte hex number. - * A length of 'zero' means end of stream (and a length of 1-3 - * would be an error). - * - * This is all pretty stupid, but we use this packetized line - * format to make a streaming format possible without ever - * over-running the read buffers. That way we'll never read - * into what might be the pack data (which should go to another - * process entirely). - * - * The writing side could use stdio, but since the reading - * side can't, we stay with pure read/write interfaces. - */ -ssize_t safe_write(int fd, const void *buf, ssize_t n) +char packet_buffer[LARGE_PACKET_MAX]; +static const char *packet_trace_prefix = "git"; +static struct trace_key trace_packet = TRACE_KEY_INIT(PACKET); +static struct trace_key trace_pack = TRACE_KEY_INIT(PACKFILE); + +void packet_trace_identity(const char *prog) { - ssize_t nn = n; - while (n) { - int ret = xwrite(fd, buf, n); - if (ret > 0) { - buf = (char *) buf + ret; - n -= ret; + packet_trace_prefix = xstrdup(prog); +} + +static int packet_trace_pack(const char *buf, unsigned int len, int sideband) +{ + if (!sideband) { + trace_verbatim(&trace_pack, buf, len); + return 1; + } else if (len && *buf == '\1') { + trace_verbatim(&trace_pack, buf + 1, len - 1); + return 1; + } else { + /* it's another non-pack sideband */ + return 0; + } +} + +static void packet_trace(const char *buf, unsigned int len, int write) +{ + int i; + struct strbuf out; + static int in_pack, sideband; + + if (!trace_want(&trace_packet) && !trace_want(&trace_pack)) + return; + + if (in_pack) { + if (packet_trace_pack(buf, len, sideband)) + return; + } else if (starts_with(buf, "PACK") || starts_with(buf, "\1PACK")) { + in_pack = 1; + sideband = *buf == '\1'; + packet_trace_pack(buf, len, sideband); + + /* + * Make a note in the human-readable trace that the pack data + * started. + */ + buf = "PACK ..."; + len = strlen(buf); + } + + if (!trace_want(&trace_packet)) + return; + + /* +32 is just a guess for header + quoting */ + strbuf_init(&out, len+32); + + strbuf_addf(&out, "packet: %12s%c ", + packet_trace_prefix, write ? '>' : '<'); + + /* XXX we should really handle printable utf8 */ + for (i = 0; i < len; i++) { + /* suppress newlines */ + if (buf[i] == '\n') continue; - } - if (!ret) - die("write error (disk full?)"); - die("write error (%s)", strerror(errno)); + if (buf[i] >= 0x20 && buf[i] <= 0x7e) + strbuf_addch(&out, buf[i]); + else + strbuf_addf(&out, "\\%o", buf[i]); } - return nn; + + strbuf_addch(&out, '\n'); + trace_strbuf(&trace_packet, &out); + strbuf_release(&out); } /* @@ -39,53 +81,94 @@ ssize_t safe_write(int fd, const void *buf, ssize_t n) */ void packet_flush(int fd) { - safe_write(fd, "0000", 4); + packet_trace("0000", 4, 1); + write_or_die(fd, "0000", 4); +} + +void packet_buf_flush(struct strbuf *buf) +{ + packet_trace("0000", 4, 1); + strbuf_add(buf, "0000", 4); } #define hex(a) (hexchar[(a) & 15]) -void packet_write(int fd, const char *fmt, ...) +static void format_packet(struct strbuf *out, const char *fmt, va_list args) { - static char buffer[1000]; static char hexchar[] = "0123456789abcdef"; + size_t orig_len, n; + + orig_len = out->len; + strbuf_addstr(out, "0000"); + strbuf_vaddf(out, fmt, args); + n = out->len - orig_len; + + if (n > LARGE_PACKET_MAX) + die("protocol error: impossibly long line"); + + out->buf[orig_len + 0] = hex(n >> 12); + out->buf[orig_len + 1] = hex(n >> 8); + out->buf[orig_len + 2] = hex(n >> 4); + out->buf[orig_len + 3] = hex(n); + packet_trace(out->buf + orig_len + 4, n - 4, 1); +} + +void packet_write(int fd, const char *fmt, ...) +{ + static struct strbuf buf = STRBUF_INIT; va_list args; - unsigned n; + strbuf_reset(&buf); va_start(args, fmt); - n = vsnprintf(buffer + 4, sizeof(buffer) - 4, fmt, args); + format_packet(&buf, fmt, args); va_end(args); - if (n >= sizeof(buffer)-4) - die("protocol error: impossibly long line"); - n += 4; - buffer[0] = hex(n >> 12); - buffer[1] = hex(n >> 8); - buffer[2] = hex(n >> 4); - buffer[3] = hex(n); - safe_write(fd, buffer, n); + write_or_die(fd, buf.buf, buf.len); } -static void safe_read(int fd, void *buffer, unsigned size) +void packet_buf_write(struct strbuf *buf, const char *fmt, ...) { - int n = 0; + va_list args; + + va_start(args, fmt); + format_packet(buf, fmt, args); + va_end(args); +} + +static int get_packet_data(int fd, char **src_buf, size_t *src_size, + void *dst, unsigned size, int options) +{ + ssize_t ret; + + if (fd >= 0 && src_buf && *src_buf) + die("BUG: multiple sources given to packet_read"); - while (n < size) { - int ret = xread(fd, (char *) buffer + n, size - n); + /* Read up to "size" bytes from our source, whatever it is. */ + if (src_buf && *src_buf) { + ret = size < *src_size ? size : *src_size; + memcpy(dst, *src_buf, ret); + *src_buf += ret; + *src_size -= ret; + } else { + ret = read_in_full(fd, dst, size); if (ret < 0) - die("read error (%s)", strerror(errno)); - if (!ret) - die("The remote end hung up unexpectedly"); - n += ret; + die_errno("read error"); } + + /* And complain if we didn't get enough bytes to satisfy the read. */ + if (ret < size) { + if (options & PACKET_READ_GENTLE_ON_EOF) + return -1; + + die("The remote end hung up unexpectedly"); + } + + return ret; } -int packet_read_line(int fd, char *buffer, unsigned size) +static int packet_length(const char *linelen) { int n; - unsigned len; - char linelen[4]; - - safe_read(fd, linelen, 4); + int len = 0; - len = 0; for (n = 0; n < 4; n++) { unsigned char c = linelen[n]; len <<= 4; @@ -101,14 +184,61 @@ int packet_read_line(int fd, char *buffer, unsigned size) len += c - 'A' + 10; continue; } - die("protocol error: bad line length character"); + return -1; } - if (!len) + return len; +} + +int packet_read(int fd, char **src_buf, size_t *src_len, + char *buffer, unsigned size, int options) +{ + int len, ret; + char linelen[4]; + + ret = get_packet_data(fd, src_buf, src_len, linelen, 4, options); + if (ret < 0) + return ret; + len = packet_length(linelen); + if (len < 0) + die("protocol error: bad line length character: %.4s", linelen); + if (!len) { + packet_trace("0000", 4, 0); return 0; + } len -= 4; if (len >= size) die("protocol error: bad line length %d", len); - safe_read(fd, buffer, len); + ret = get_packet_data(fd, src_buf, src_len, buffer, len, options); + if (ret < 0) + return ret; + + if ((options & PACKET_READ_CHOMP_NEWLINE) && + len && buffer[len-1] == '\n') + len--; + buffer[len] = 0; + packet_trace(buffer, len, 0); return len; } + +static char *packet_read_line_generic(int fd, + char **src, size_t *src_len, + int *dst_len) +{ + int len = packet_read(fd, src, src_len, + packet_buffer, sizeof(packet_buffer), + PACKET_READ_CHOMP_NEWLINE); + if (dst_len) + *dst_len = len; + return len ? packet_buffer : NULL; +} + +char *packet_read_line(int fd, int *len_p) +{ + return packet_read_line_generic(fd, NULL, NULL, len_p); +} + +char *packet_read_line_buf(char **src, size_t *src_len, int *dst_len) +{ + return packet_read_line_generic(-1, src, src_len, dst_len); +} |