Clearify the documentation for core.ignoreStat
[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
10 static const char upload_archive_usage[] =
11         "git-upload-archive <repo>";
12
13 static const char deadchild[] =
14 "git-upload-archive: archiver died with error";
15
16 static const char lostchild[] =
17 "git-upload-archive: archiver process was lost";
18
19
20 static int run_upload_archive(int argc, const char **argv, const char *prefix)
21 {
22         struct archiver ar;
23         const char *sent_argv[MAX_ARGS];
24         const char *arg_cmd = "argument ";
25         char *p, buf[4096];
26         int treeish_idx;
27         int sent_argc;
28         int len;
29
30         if (argc != 2)
31                 usage(upload_archive_usage);
32
33         if (strlen(argv[1]) > sizeof(buf))
34                 die("insanely long repository name");
35
36         strcpy(buf, argv[1]); /* enter-repo smudges its argument */
37
38         if (!enter_repo(buf, 0))
39                 die("not a git archive");
40
41         /* put received options in sent_argv[] */
42         sent_argc = 1;
43         sent_argv[0] = "git-upload-archive";
44         for (p = buf;;) {
45                 /* This will die if not enough free space in buf */
46                 len = packet_read_line(0, p, (buf + sizeof buf) - p);
47                 if (len == 0)
48                         break;  /* got a flush */
49                 if (sent_argc > MAX_ARGS - 2)
50                         die("Too many options (>29)");
51
52                 if (p[len-1] == '\n') {
53                         p[--len] = 0;
54                 }
55                 if (len < strlen(arg_cmd) ||
56                     strncmp(arg_cmd, p, strlen(arg_cmd)))
57                         die("'argument' token or flush expected");
58
59                 len -= strlen(arg_cmd);
60                 memmove(p, p + strlen(arg_cmd), len);
61                 sent_argv[sent_argc++] = p;
62                 p += len;
63                 *p++ = 0;
64         }
65         sent_argv[sent_argc] = NULL;
66
67         /* parse all options sent by the client */
68         treeish_idx = parse_archive_args(sent_argc, sent_argv, &ar);
69
70         parse_treeish_arg(sent_argv + treeish_idx, &ar.args, prefix);
71         parse_pathspec_arg(sent_argv + treeish_idx + 1, &ar.args);
72
73         return ar.write_archive(&ar.args);
74 }
75
76 static void error_clnt(const char *fmt, ...)
77 {
78         char buf[1024];
79         va_list params;
80         int len;
81
82         va_start(params, fmt);
83         len = vsprintf(buf, fmt, params);
84         va_end(params);
85         send_sideband(1, 3, buf, len, LARGE_PACKET_MAX);
86         die("sent error to the client: %s", buf);
87 }
88
89 static void process_input(int child_fd, int band)
90 {
91         char buf[16384];
92         ssize_t sz = read(child_fd, buf, sizeof(buf));
93         if (sz < 0) {
94                 if (errno != EAGAIN && errno != EINTR)
95                         error_clnt("read error: %s\n", strerror(errno));
96                 return;
97         }
98         send_sideband(1, band, buf, sz, LARGE_PACKET_MAX);
99 }
100
101 int cmd_upload_archive(int argc, const char **argv, const char *prefix)
102 {
103         pid_t writer;
104         int fd1[2], fd2[2];
105         /*
106          * Set up sideband subprocess.
107          *
108          * We (parent) monitor and read from child, sending its fd#1 and fd#2
109          * multiplexed out to our fd#1.  If the child dies, we tell the other
110          * end over channel #3.
111          */
112         if (pipe(fd1) < 0 || pipe(fd2) < 0) {
113                 int err = errno;
114                 packet_write(1, "NACK pipe failed on the remote side\n");
115                 die("upload-archive: %s", strerror(err));
116         }
117         writer = fork();
118         if (writer < 0) {
119                 int err = errno;
120                 packet_write(1, "NACK fork failed on the remote side\n");
121                 die("upload-archive: %s", strerror(err));
122         }
123         if (!writer) {
124                 /* child - connect fd#1 and fd#2 to the pipe */
125                 dup2(fd1[1], 1);
126                 dup2(fd2[1], 2);
127                 close(fd1[1]); close(fd2[1]);
128                 close(fd1[0]); close(fd2[0]); /* we do not read from pipe */
129
130                 exit(run_upload_archive(argc, argv, prefix));
131         }
132
133         /* parent - read from child, multiplex and send out to fd#1 */
134         close(fd1[1]); close(fd2[1]); /* we do not write to pipe */
135         packet_write(1, "ACK\n");
136         packet_flush(1);
137
138         while (1) {
139                 struct pollfd pfd[2];
140                 int status;
141
142                 pfd[0].fd = fd1[0];
143                 pfd[0].events = POLLIN;
144                 pfd[1].fd = fd2[0];
145                 pfd[1].events = POLLIN;
146                 if (poll(pfd, 2, -1) < 0) {
147                         if (errno != EINTR) {
148                                 error("poll failed resuming: %s",
149                                       strerror(errno));
150                                 sleep(1);
151                         }
152                         continue;
153                 }
154                 if (pfd[0].revents & POLLIN)
155                         /* Data stream ready */
156                         process_input(pfd[0].fd, 1);
157                 if (pfd[1].revents & POLLIN)
158                         /* Status stream ready */
159                         process_input(pfd[1].fd, 2);
160                 /* Always finish to read data when available */
161                 if ((pfd[0].revents | pfd[1].revents) & POLLIN)
162                         continue;
163
164                 if (waitpid(writer, &status, 0) < 0)
165                         error_clnt("%s", lostchild);
166                 else if (!WIFEXITED(status) || WEXITSTATUS(status) > 0)
167                         error_clnt("%s", deadchild);
168                 packet_flush(1);
169                 break;
170         }
171         return 0;
172 }