index-pack: work around thread-unsafe pread()
[git] / builtin / upload-archive.c
1 /*
2  * Copyright (c) 2006 Franck Bui-Huu
3  */
4 #include "cache.h"
5 #include "builtin.h"
6 #include "archive.h"
7 #include "pkt-line.h"
8 #include "sideband.h"
9 #include "run-command.h"
10 #include "argv-array.h"
11
12 static const char upload_archive_usage[] =
13         "git upload-archive <repo>";
14
15 static const char deadchild[] =
16 "git upload-archive: archiver died with error";
17
18 #define MAX_ARGS (64)
19
20 int cmd_upload_archive_writer(int argc, const char **argv, const char *prefix)
21 {
22         struct argv_array sent_argv = ARGV_ARRAY_INIT;
23         const char *arg_cmd = "argument ";
24
25         if (argc != 2)
26                 usage(upload_archive_usage);
27
28         if (!enter_repo(argv[1], 0))
29                 die("'%s' does not appear to be a git repository", argv[1]);
30
31         /* put received options in sent_argv[] */
32         argv_array_push(&sent_argv, "git-upload-archive");
33         for (;;) {
34                 char *buf = packet_read_line(0, NULL);
35                 if (!buf)
36                         break;  /* got a flush */
37                 if (sent_argv.argc > MAX_ARGS)
38                         die("Too many options (>%d)", MAX_ARGS - 1);
39
40                 if (!starts_with(buf, arg_cmd))
41                         die("'argument' token or flush expected");
42                 argv_array_push(&sent_argv, buf + strlen(arg_cmd));
43         }
44
45         /* parse all options sent by the client */
46         return write_archive(sent_argv.argc, sent_argv.argv, prefix, 0, NULL, 1);
47 }
48
49 __attribute__((format (printf, 1, 2)))
50 static void error_clnt(const char *fmt, ...)
51 {
52         char buf[1024];
53         va_list params;
54         int len;
55
56         va_start(params, fmt);
57         len = vsprintf(buf, fmt, params);
58         va_end(params);
59         send_sideband(1, 3, buf, len, LARGE_PACKET_MAX);
60         die("sent error to the client: %s", buf);
61 }
62
63 static ssize_t process_input(int child_fd, int band)
64 {
65         char buf[16384];
66         ssize_t sz = read(child_fd, buf, sizeof(buf));
67         if (sz < 0) {
68                 if (errno != EAGAIN && errno != EINTR)
69                         error_clnt("read error: %s\n", strerror(errno));
70                 return sz;
71         }
72         send_sideband(1, band, buf, sz, LARGE_PACKET_MAX);
73         return sz;
74 }
75
76 int cmd_upload_archive(int argc, const char **argv, const char *prefix)
77 {
78         struct child_process writer = { argv };
79
80         /*
81          * Set up sideband subprocess.
82          *
83          * We (parent) monitor and read from child, sending its fd#1 and fd#2
84          * multiplexed out to our fd#1.  If the child dies, we tell the other
85          * end over channel #3.
86          */
87         argv[0] = "upload-archive--writer";
88         writer.out = writer.err = -1;
89         writer.git_cmd = 1;
90         if (start_command(&writer)) {
91                 int err = errno;
92                 packet_write(1, "NACK unable to spawn subprocess\n");
93                 die("upload-archive: %s", strerror(err));
94         }
95
96         packet_write(1, "ACK\n");
97         packet_flush(1);
98
99         while (1) {
100                 struct pollfd pfd[2];
101
102                 pfd[0].fd = writer.out;
103                 pfd[0].events = POLLIN;
104                 pfd[1].fd = writer.err;
105                 pfd[1].events = POLLIN;
106                 if (poll(pfd, 2, -1) < 0) {
107                         if (errno != EINTR) {
108                                 error("poll failed resuming: %s",
109                                       strerror(errno));
110                                 sleep(1);
111                         }
112                         continue;
113                 }
114                 if (pfd[1].revents & POLLIN)
115                         /* Status stream ready */
116                         if (process_input(pfd[1].fd, 2))
117                                 continue;
118                 if (pfd[0].revents & POLLIN)
119                         /* Data stream ready */
120                         if (process_input(pfd[0].fd, 1))
121                                 continue;
122
123                 if (finish_command(&writer))
124                         error_clnt("%s", deadchild);
125                 packet_flush(1);
126                 break;
127         }
128         return 0;
129 }