From f3a3214e83be2905c57eff5d9035d169cae4644e Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Wed, 29 Jun 2005 20:50:15 -0700 Subject: [PATCH] Make send/receive-pack be closer to doing something interesting --- Makefile | 7 +-- pkt-line.c | 117 +++++++++++++++++++++++++++++++++++++++++++++ pkt-line.h | 12 +++++ receive-pack.c | 126 +++---------------------------------------------- send-pack.c | 12 +++-- 5 files changed, 148 insertions(+), 126 deletions(-) create mode 100644 pkt-line.c create mode 100644 pkt-line.h diff --git a/Makefile b/Makefile index 792b01445..94f5d9e5f 100644 --- a/Makefile +++ b/Makefile @@ -9,7 +9,7 @@ # BREAK YOUR LOCAL DIFFS! show-diff and anything using it will likely randomly # break unless your underlying filesystem supports those sub-second times # (my ext3 doesn't). -COPTS=-O2 +COPTS= CFLAGS=-g $(COPTS) -Wall prefix=$(HOME) @@ -46,9 +46,10 @@ install: $(PROG) $(SCRIPTS) LIB_OBJS=read-cache.o sha1_file.o usage.o object.o commit.o tree.o blob.o \ tag.o date.o index.o diff-delta.o patch-delta.o entry.o \ - epoch.o refs.o csum-file.o verify_pack.o + epoch.o refs.o csum-file.o verify_pack.o pkt-line.o LIB_FILE=libgit.a -LIB_H=cache.h object.h blob.h tree.h commit.h tag.h delta.h epoch.h csum-file.h pack.h +LIB_H=cache.h object.h blob.h tree.h commit.h tag.h delta.h epoch.h csum-file.h \ + pack.h pkt-line.h LIB_H += strbuf.h LIB_OBJS += strbuf.o diff --git a/pkt-line.c b/pkt-line.c new file mode 100644 index 000000000..69473046b --- /dev/null +++ b/pkt-line.c @@ -0,0 +1,117 @@ +#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. + */ +static void safe_write(int fd, const void *buf, unsigned n) +{ + while (n) { + int ret = write(fd, buf, n); + if (ret > 0) { + buf += ret; + n -= ret; + continue; + } + if (!ret) + die("write error (disk full?)"); + if (errno == EAGAIN || errno == EINTR) + continue; + die("write error (%s)", strerror(errno)); + } +} + +/* + * If we buffered things up above (we don't, but we should), + * we'd flush it here + */ +void packet_flush(int fd) +{ + safe_write(fd, "0000", 4); +} + +#define hex(a) (hexchar[(a) & 15]) +void packet_write(int fd, const char *fmt, ...) +{ + static char buffer[1000]; + static char hexchar[] = "0123456789abcdef"; + va_list args; + unsigned n; + + va_start(args, fmt); + n = vsnprintf(buffer + 4, sizeof(buffer) - 4, 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); +} + +static void safe_read(int fd, void *buffer, unsigned size) +{ + int n = 0; + + while (n < size) { + int ret = read(fd, buffer + n, size - n); + if (ret < 0) { + if (errno == EINTR || errno == EAGAIN) + continue; + die("read error (%s)", strerror(errno)); + } + if (!ret) + die("unexpected EOF"); + n += ret; + } +} + +int packet_read_line(int fd, char *buffer, unsigned size) +{ + int n; + unsigned len; + char linelen[4]; + + safe_read(fd, linelen, 4); + + len = 0; + for (n = 0; n < 4; n++) { + unsigned char c = linelen[n]; + len <<= 4; + if (c >= '0' && c <= '9') { + len += c - '0'; + continue; + } + if (c >= 'a' && c <= 'f') { + len += c - 'a' + 10; + continue; + } + if (c >= 'A' && c <= 'F') { + len += c - 'A' + 10; + continue; + } + die("protocol error: bad line length character"); + } + if (!len) + return 0; + len -= 4; + if (len >= size) + die("protocol error: bad line length %d", len); + safe_read(fd, buffer, len); + buffer[len] = 0; + return len; +} diff --git a/pkt-line.h b/pkt-line.h new file mode 100644 index 000000000..b0b4f6d49 --- /dev/null +++ b/pkt-line.h @@ -0,0 +1,12 @@ +#ifndef PKTLINE_H +#define PKTLINE_H + +/* + * Silly packetized line writing interface + */ +void packet_flush(int fd); +void packet_write(int fd, const char *fmt, ...); + +int packet_read_line(int fd, char *buffer, unsigned size); + +#endif diff --git a/receive-pack.c b/receive-pack.c index 601388314..13d0b668f 100644 --- a/receive-pack.c +++ b/receive-pack.c @@ -1,4 +1,5 @@ #include "cache.h" +#include "pkt-line.h" #include static const char receive_pack_usage[] = "git-receive-pack [--unpack=executable] [heads]"; @@ -26,61 +27,9 @@ static int path_match(const char *path, int nr, char **match) return 0; } -static void safe_write(int fd, const void *buf, unsigned n) -{ - while (n) { - int ret = write(fd, buf, n); - if (ret > 0) { - buf += ret; - n -= ret; - continue; - } - if (!ret) - die("write error (disk full?)"); - if (errno == EAGAIN || errno == EINTR) - continue; - die("write error (%s)", strerror(errno)); - } -} - -/* - * If we buffered things up above (we don't, but we should), - * we'd flush it here - */ -static void flush_safe(int fd) -{ -} - -/* - * 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). - */ -#define hex(a) (hexchar[(a) & 15]) -static void packet_write(const char *fmt, ...) -{ - static char buffer[1000]; - static char hexchar[] = "0123456789abcdef"; - va_list args; - unsigned n; - - va_start(args, fmt); - n = vsnprintf(buffer + 4, sizeof(buffer) - 4, 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(1, buffer, n); -} - static void show_ref(const char *path, unsigned char *sha1) { - packet_write("%s %s\n", sha1_to_hex(sha1), path); + packet_write(1, "%s %s\n", sha1_to_hex(sha1), path); } static int read_ref(const char *path, unsigned char *sha1) @@ -137,66 +86,6 @@ static void write_head_info(const char *base, int nr, char **match) } } -/* - * 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. - */ -static void safe_read(int fd, void *buffer, unsigned size) -{ - int n = 0; - - while (n < size) { - int ret = read(0, buffer + n, size - n); - if (ret < 0) { - if (errno == EINTR || errno == EAGAIN) - continue; - die("read error (%s)", strerror(errno)); - } - if (!ret) - die("unexpected EOF"); - n += ret; - } -} - -static int safe_read_line(char *buffer, unsigned size) -{ - int n, len; - - safe_read(0, buffer, 4); - - len = 0; - for (n = 0; n < 4; n++) { - unsigned char c = buffer[n]; - len <<= 4; - if (c >= '0' && c <= '9') { - len += c - '0'; - continue; - } - if (c >= 'a' && c <= 'f') { - len += c - 'a' + 10; - continue; - } - if (c >= 'A' && c <= 'F') { - len += c - 'A' + 10; - continue; - } - die("protocol error: bad line length character"); - } - if (!len) - return 0; - if (len < 4 || len >= size) - die("protocol error: bad line length %d", len); - safe_read(0, buffer + 4, len - 4); - buffer[len] = 0; - return len; -} - struct line { struct line *next; char data[0]; @@ -213,7 +102,7 @@ static void execute_commands(void) struct line *line = commands; while (line) { - printf("%s", line->data); + fprintf(stderr, "%s", line->data); line = line->next; } } @@ -223,7 +112,7 @@ static void read_head_info(void) struct line **p = &commands; for (;;) { static char line[1000]; - int len = safe_read_line(line, sizeof(line)); + int len = packet_read_line(0, line, sizeof(line)); struct line *n; if (!len) break; @@ -242,8 +131,8 @@ static void unpack(void) if (pid < 0) die("unpack fork failed"); if (!pid) { - char *const envp[] = { "GIT_DIR=.", NULL }; - execle(unpacker, unpacker, NULL, envp); + setenv("GIT_DIR", ".", 1); + execlp(unpacker, unpacker, NULL); die("unpack execute failed"); } @@ -311,8 +200,7 @@ int main(int argc, char **argv) write_head_info("refs/", nr_heads, heads); /* EOF */ - safe_write(1, "0000", 4); - flush_safe(1); + packet_flush(1); read_head_info(); unpack(); diff --git a/send-pack.c b/send-pack.c index af57d4028..99cb84b2c 100644 --- a/send-pack.c +++ b/send-pack.c @@ -1,4 +1,5 @@ #include "cache.h" +#include "pkt-line.h" static const char send_pack_usage[] = "git-send-pack [--exec=other] destination [heads]*"; @@ -8,13 +9,16 @@ static int send_pack(int in, int out) { for (;;) { static char buffer[1000]; - int ret = read(in, buffer, sizeof(buffer)); - if (ret > 0) { - write(1, buffer, ret); + int len; + + len = packet_read_line(in, buffer, sizeof(buffer)); + if (len > 0) { + write(2, buffer, len); continue; } break; } + packet_flush(out); close(out); return 0; } @@ -77,7 +81,7 @@ static int setup_connection(int fd[2], char *url, char **heads) if (host) execlp("ssh", "ssh", host, command, NULL); else - execlp(host, command, NULL); + execlp("sh", "sh", "-c", command, NULL); die("exec failed"); } fd[0] = pipefd[0][0]; -- 2.26.2