From 1b593e1ea4d2af0f6444d9a7788d5d99abd6fde5 Mon Sep 17 00:00:00 2001 From: Vincent Ambo Date: Sat, 11 Jan 2020 23:36:56 +0000 Subject: Squashed 'third_party/git/' content from commit cb71568594 git-subtree-dir: third_party/git git-subtree-split: cb715685942260375e1eb8153b0768a376e4ece7 --- pkt-line.c | 570 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 570 insertions(+) create mode 100644 pkt-line.c (limited to 'pkt-line.c') diff --git a/pkt-line.c b/pkt-line.c new file mode 100644 index 000000000000..a0e87b1e8140 --- /dev/null +++ b/pkt-line.c @@ -0,0 +1,570 @@ +#include "cache.h" +#include "pkt-line.h" +#include "run-command.h" + +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) +{ + packet_trace_prefix = xstrdup(prog); +} + +static const char *get_trace_prefix(void) +{ + return in_async() ? "sideband" : packet_trace_prefix; +} + +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 ", + get_trace_prefix(), write ? '>' : '<'); + + /* XXX we should really handle printable utf8 */ + for (i = 0; i < len; i++) { + /* suppress newlines */ + if (buf[i] == '\n') + continue; + if (buf[i] >= 0x20 && buf[i] <= 0x7e) + strbuf_addch(&out, buf[i]); + else + strbuf_addf(&out, "\\%o", buf[i]); + } + + strbuf_addch(&out, '\n'); + trace_strbuf(&trace_packet, &out); + strbuf_release(&out); +} + +/* + * 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); + if (write_in_full(fd, "0000", 4) < 0) + die_errno(_("unable to write flush packet")); +} + +void packet_delim(int fd) +{ + packet_trace("0001", 4, 1); + if (write_in_full(fd, "0001", 4) < 0) + die_errno(_("unable to write delim packet")); +} + +int packet_flush_gently(int fd) +{ + packet_trace("0000", 4, 1); + if (write_in_full(fd, "0000", 4) < 0) + return error(_("flush packet write failed")); + return 0; +} + +void packet_buf_flush(struct strbuf *buf) +{ + packet_trace("0000", 4, 1); + strbuf_add(buf, "0000", 4); +} + +void packet_buf_delim(struct strbuf *buf) +{ + packet_trace("0001", 4, 1); + strbuf_add(buf, "0001", 4); +} + +void set_packet_header(char *buf, int size) +{ + static char hexchar[] = "0123456789abcdef"; + + #define hex(a) (hexchar[(a) & 15]) + buf[0] = hex(size >> 12); + buf[1] = hex(size >> 8); + buf[2] = hex(size >> 4); + buf[3] = hex(size); + #undef hex +} + +static void format_packet(struct strbuf *out, const char *prefix, + const char *fmt, va_list args) +{ + size_t orig_len, n; + + orig_len = out->len; + strbuf_addstr(out, "0000"); + strbuf_addstr(out, prefix); + strbuf_vaddf(out, fmt, args); + n = out->len - orig_len; + + if (n > LARGE_PACKET_MAX) + die(_("protocol error: impossibly long line")); + + set_packet_header(&out->buf[orig_len], n); + packet_trace(out->buf + orig_len + 4, n - 4, 1); +} + +static int packet_write_fmt_1(int fd, int gently, const char *prefix, + const char *fmt, va_list args) +{ + static struct strbuf buf = STRBUF_INIT; + + strbuf_reset(&buf); + format_packet(&buf, prefix, fmt, args); + if (write_in_full(fd, buf.buf, buf.len) < 0) { + if (!gently) { + check_pipe(errno); + die_errno(_("packet write with format failed")); + } + return error(_("packet write with format failed")); + } + + return 0; +} + +void packet_write_fmt(int fd, const char *fmt, ...) +{ + va_list args; + + va_start(args, fmt); + packet_write_fmt_1(fd, 0, "", fmt, args); + va_end(args); +} + +int packet_write_fmt_gently(int fd, const char *fmt, ...) +{ + int status; + va_list args; + + va_start(args, fmt); + status = packet_write_fmt_1(fd, 1, "", fmt, args); + va_end(args); + return status; +} + +static int packet_write_gently(const int fd_out, const char *buf, size_t size) +{ + static char packet_write_buffer[LARGE_PACKET_MAX]; + size_t packet_size; + + if (size > sizeof(packet_write_buffer) - 4) + return error(_("packet write failed - data exceeds max packet size")); + + packet_trace(buf, size, 1); + packet_size = size + 4; + set_packet_header(packet_write_buffer, packet_size); + memcpy(packet_write_buffer + 4, buf, size); + if (write_in_full(fd_out, packet_write_buffer, packet_size) < 0) + return error(_("packet write failed")); + return 0; +} + +void packet_write(int fd_out, const char *buf, size_t size) +{ + if (packet_write_gently(fd_out, buf, size)) + die_errno(_("packet write failed")); +} + +void packet_buf_write(struct strbuf *buf, const char *fmt, ...) +{ + va_list args; + + va_start(args, fmt); + format_packet(buf, "", fmt, args); + va_end(args); +} + +void packet_buf_write_len(struct strbuf *buf, const char *data, size_t len) +{ + size_t orig_len, n; + + orig_len = buf->len; + strbuf_addstr(buf, "0000"); + strbuf_add(buf, data, len); + n = buf->len - orig_len; + + if (n > LARGE_PACKET_MAX) + die(_("protocol error: impossibly long line")); + + set_packet_header(&buf->buf[orig_len], n); + packet_trace(data, len, 1); +} + +int write_packetized_from_fd(int fd_in, int fd_out) +{ + static char buf[LARGE_PACKET_DATA_MAX]; + int err = 0; + ssize_t bytes_to_write; + + while (!err) { + bytes_to_write = xread(fd_in, buf, sizeof(buf)); + if (bytes_to_write < 0) + return COPY_READ_ERROR; + if (bytes_to_write == 0) + break; + err = packet_write_gently(fd_out, buf, bytes_to_write); + } + if (!err) + err = packet_flush_gently(fd_out); + return err; +} + +int write_packetized_from_buf(const char *src_in, size_t len, int fd_out) +{ + int err = 0; + size_t bytes_written = 0; + size_t bytes_to_write; + + while (!err) { + if ((len - bytes_written) > LARGE_PACKET_DATA_MAX) + bytes_to_write = LARGE_PACKET_DATA_MAX; + else + bytes_to_write = len - bytes_written; + if (bytes_to_write == 0) + break; + err = packet_write_gently(fd_out, src_in + bytes_written, bytes_to_write); + bytes_written += bytes_to_write; + } + if (!err) + err = packet_flush_gently(fd_out); + return err; +} + +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) + 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) +{ + int val = hex2chr(linelen); + return (val < 0) ? val : (val << 8) | hex2chr(linelen + 2); +} + +enum packet_read_status packet_read_with_status(int fd, char **src_buffer, + size_t *src_len, char *buffer, + unsigned size, int *pktlen, + int options) +{ + int len; + char linelen[4]; + + if (get_packet_data(fd, src_buffer, src_len, linelen, 4, options) < 0) { + *pktlen = -1; + return PACKET_READ_EOF; + } + + len = packet_length(linelen); + + if (len < 0) { + die(_("protocol error: bad line length character: %.4s"), linelen); + } else if (!len) { + packet_trace("0000", 4, 0); + *pktlen = 0; + return PACKET_READ_FLUSH; + } else if (len == 1) { + packet_trace("0001", 4, 0); + *pktlen = 0; + return PACKET_READ_DELIM; + } else if (len < 4) { + die(_("protocol error: bad line length %d"), len); + } + + len -= 4; + if ((unsigned)len >= size) + die(_("protocol error: bad line length %d"), len); + + if (get_packet_data(fd, src_buffer, src_len, buffer, len, options) < 0) { + *pktlen = -1; + return PACKET_READ_EOF; + } + + if ((options & PACKET_READ_CHOMP_NEWLINE) && + len && buffer[len-1] == '\n') + len--; + + buffer[len] = 0; + packet_trace(buffer, len, 0); + + if ((options & PACKET_READ_DIE_ON_ERR_PACKET) && + starts_with(buffer, "ERR ")) + die(_("remote error: %s"), buffer + 4); + + *pktlen = len; + return PACKET_READ_NORMAL; +} + +int packet_read(int fd, char **src_buffer, size_t *src_len, + char *buffer, unsigned size, int options) +{ + int pktlen = -1; + + packet_read_with_status(fd, src_buffer, src_len, buffer, size, + &pktlen, options); + + return pktlen; +} + +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 > 0) ? packet_buffer : NULL; +} + +char *packet_read_line(int fd, int *len_p) +{ + return packet_read_line_generic(fd, NULL, NULL, len_p); +} + +int packet_read_line_gently(int fd, int *dst_len, char **dst_line) +{ + int len = packet_read(fd, NULL, NULL, + packet_buffer, sizeof(packet_buffer), + PACKET_READ_CHOMP_NEWLINE|PACKET_READ_GENTLE_ON_EOF); + if (dst_len) + *dst_len = len; + if (dst_line) + *dst_line = (len > 0) ? packet_buffer : NULL; + 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); +} + +ssize_t read_packetized_to_strbuf(int fd_in, struct strbuf *sb_out) +{ + int packet_len; + + size_t orig_len = sb_out->len; + size_t orig_alloc = sb_out->alloc; + + for (;;) { + strbuf_grow(sb_out, LARGE_PACKET_DATA_MAX); + packet_len = packet_read(fd_in, NULL, NULL, + /* strbuf_grow() above always allocates one extra byte to + * store a '\0' at the end of the string. packet_read() + * writes a '\0' extra byte at the end, too. Let it know + * that there is already room for the extra byte. + */ + sb_out->buf + sb_out->len, LARGE_PACKET_DATA_MAX+1, + PACKET_READ_GENTLE_ON_EOF); + if (packet_len <= 0) + break; + sb_out->len += packet_len; + } + + if (packet_len < 0) { + if (orig_alloc == 0) + strbuf_release(sb_out); + else + strbuf_setlen(sb_out, orig_len); + return packet_len; + } + return sb_out->len - orig_len; +} + +int recv_sideband(const char *me, int in_stream, int out) +{ + char buf[LARGE_PACKET_MAX + 1]; + int len; + struct strbuf scratch = STRBUF_INIT; + enum sideband_type sideband_type; + + while (1) { + len = packet_read(in_stream, NULL, NULL, buf, LARGE_PACKET_MAX, + 0); + if (!demultiplex_sideband(me, buf, len, 0, &scratch, + &sideband_type)) + continue; + switch (sideband_type) { + case SIDEBAND_PRIMARY: + write_or_die(out, buf + 1, len - 1); + break; + default: /* errors: message already written */ + return sideband_type; + } + } +} + +/* Packet Reader Functions */ +void packet_reader_init(struct packet_reader *reader, int fd, + char *src_buffer, size_t src_len, + int options) +{ + memset(reader, 0, sizeof(*reader)); + + reader->fd = fd; + reader->src_buffer = src_buffer; + reader->src_len = src_len; + reader->buffer = packet_buffer; + reader->buffer_size = sizeof(packet_buffer); + reader->options = options; + reader->me = "git"; +} + +enum packet_read_status packet_reader_read(struct packet_reader *reader) +{ + struct strbuf scratch = STRBUF_INIT; + + if (reader->line_peeked) { + reader->line_peeked = 0; + return reader->status; + } + + /* + * Consume all progress packets until a primary payload packet is + * received + */ + while (1) { + enum sideband_type sideband_type; + reader->status = packet_read_with_status(reader->fd, + &reader->src_buffer, + &reader->src_len, + reader->buffer, + reader->buffer_size, + &reader->pktlen, + reader->options); + if (!reader->use_sideband) + break; + if (demultiplex_sideband(reader->me, reader->buffer, + reader->pktlen, 1, &scratch, + &sideband_type)) + break; + } + + if (reader->status == PACKET_READ_NORMAL) + /* Skip the sideband designator if sideband is used */ + reader->line = reader->use_sideband ? + reader->buffer + 1 : reader->buffer; + else + reader->line = NULL; + + return reader->status; +} + +enum packet_read_status packet_reader_peek(struct packet_reader *reader) +{ + /* Only allow peeking a single line */ + if (reader->line_peeked) + return reader->status; + + /* Peek a line by reading it and setting peeked flag */ + packet_reader_read(reader); + reader->line_peeked = 1; + return reader->status; +} + +void packet_writer_init(struct packet_writer *writer, int dest_fd) +{ + writer->dest_fd = dest_fd; + writer->use_sideband = 0; +} + +void packet_writer_write(struct packet_writer *writer, const char *fmt, ...) +{ + va_list args; + + va_start(args, fmt); + packet_write_fmt_1(writer->dest_fd, 0, + writer->use_sideband ? "\001" : "", fmt, args); + va_end(args); +} + +void packet_writer_error(struct packet_writer *writer, const char *fmt, ...) +{ + va_list args; + + va_start(args, fmt); + packet_write_fmt_1(writer->dest_fd, 0, + writer->use_sideband ? "\003" : "ERR ", fmt, args); + va_end(args); +} + +void packet_writer_delim(struct packet_writer *writer) +{ + packet_delim(writer->dest_fd); +} + +void packet_writer_flush(struct packet_writer *writer) +{ + packet_flush(writer->dest_fd); +} -- cgit 1.4.1