diff options
Diffstat (limited to 'pkt-line.c')
-rw-r--r-- | pkt-line.c | 176 |
1 files changed, 85 insertions, 91 deletions
diff --git a/pkt-line.c b/pkt-line.c index 5a04984ea3..187a2293e7 100644 --- a/pkt-line.c +++ b/pkt-line.c @@ -1,8 +1,9 @@ #include "cache.h" #include "pkt-line.h" +char packet_buffer[LARGE_PACKET_MAX]; static const char *packet_trace_prefix = "git"; -static const char trace_key[] = "GIT_TRACE_PACKET"; +static struct trace_key trace_packet = TRACE_KEY_INIT(PACKET); void packet_trace_identity(const char *prog) { @@ -14,7 +15,7 @@ static void packet_trace(const char *buf, unsigned int len, int write) int i; struct strbuf out; - if (!trace_want(trace_key)) + if (!trace_want(&trace_packet)) return; /* +32 is just a guess for header + quoting */ @@ -23,10 +24,10 @@ static void packet_trace(const char *buf, unsigned int len, int write) strbuf_addf(&out, "packet: %12s%c ", packet_trace_prefix, write ? '>' : '<'); - if ((len >= 4 && !prefixcmp(buf, "PACK")) || - (len >= 5 && !prefixcmp(buf+1, "PACK"))) { + if ((len >= 4 && starts_with(buf, "PACK")) || + (len >= 5 && starts_with(buf+1, "PACK"))) { strbuf_addstr(&out, "PACK ..."); - unsetenv(trace_key); + trace_disable(&trace_packet); } else { /* XXX we should really handle printable utf8 */ @@ -42,50 +43,18 @@ static void packet_trace(const char *buf, unsigned int len, int write) } strbuf_addch(&out, '\n'); - trace_strbuf(trace_key, &out); + trace_strbuf(&trace_packet, &out); strbuf_release(&out); } /* - * 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) -{ - ssize_t nn = n; - while (n) { - int ret = xwrite(fd, buf, n); - if (ret > 0) { - buf = (char *) buf + ret; - n -= ret; - continue; - } - if (!ret) - die("write error (disk full?)"); - die_errno("write error"); - } - return nn; -} - -/* * If we buffered things up above (we don't, but we should), * we'd flush it here */ void packet_flush(int fd) { packet_trace("0000", 4, 1); - safe_write(fd, "0000", 4); + write_or_die(fd, "0000", 4); } void packet_buf_flush(struct strbuf *buf) @@ -95,53 +64,76 @@ void packet_buf_flush(struct strbuf *buf) } #define hex(a) (hexchar[(a) & 15]) -static char buffer[1000]; -static unsigned format_packet(const char *fmt, va_list args) +static void format_packet(struct strbuf *out, const char *fmt, va_list args) { static char hexchar[] = "0123456789abcdef"; - unsigned n; + size_t orig_len, n; + + orig_len = out->len; + strbuf_addstr(out, "0000"); + strbuf_vaddf(out, fmt, args); + n = out->len - orig_len; - n = vsnprintf(buffer + 4, sizeof(buffer) - 4, fmt, args); - if (n >= sizeof(buffer)-4) + if (n > LARGE_PACKET_MAX) 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); - packet_trace(buffer+4, n-4, 1); - return n; + + 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 = format_packet(fmt, args); + format_packet(&buf, fmt, args); va_end(args); - safe_write(fd, buffer, n); + write_or_die(fd, buf.buf, buf.len); } void packet_buf_write(struct strbuf *buf, const char *fmt, ...) { va_list args; - unsigned n; va_start(args, fmt); - n = format_packet(fmt, args); + format_packet(buf, fmt, args); va_end(args); - strbuf_add(buf, buffer, n); } -static void safe_read(int fd, void *buffer, unsigned size) +static int get_packet_data(int fd, char **src_buf, size_t *src_size, + void *dst, unsigned size, int options) { - ssize_t ret = read_in_full(fd, buffer, size); - if (ret < 0) - die_errno("read error"); - else if (ret < size) + ssize_t ret; + + if (fd >= 0 && src_buf && *src_buf) + die("BUG: multiple sources given to packet_read"); + + /* 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_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; } static int packet_length(const char *linelen) @@ -169,12 +161,15 @@ static int packet_length(const char *linelen) return len; } -int packet_read_line(int fd, char *buffer, unsigned size) +int packet_read(int fd, char **src_buf, size_t *src_len, + char *buffer, unsigned size, int options) { - int len; + int len, ret; char linelen[4]; - safe_read(fd, 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); @@ -185,38 +180,37 @@ int packet_read_line(int fd, char *buffer, unsigned size) 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; } -int packet_get_line(struct strbuf *out, - char **src_buf, size_t *src_len) +static char *packet_read_line_generic(int fd, + char **src, size_t *src_len, + int *dst_len) { - int len; - - if (*src_len < 4) - return -1; - len = packet_length(*src_buf); - if (len < 0) - return -1; - if (!len) { - *src_buf += 4; - *src_len -= 4; - packet_trace("0000", 4, 0); - return 0; - } - if (*src_len < len) - return -2; + 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; +} - *src_buf += 4; - *src_len -= 4; - len -= 4; +char *packet_read_line(int fd, int *len_p) +{ + return packet_read_line_generic(fd, NULL, NULL, len_p); +} - strbuf_add(out, *src_buf, len); - *src_buf += len; - *src_len -= len; - packet_trace(out->buf, out->len, 0); - return len; +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); } |