| 1 | /* This program can record the stream of data flowing to or from a program. |
| 2 | * This allows it to be used to check that rsync's data that is flowing |
| 3 | * through a remote shell is not being corrupted (for example). |
| 4 | * |
| 5 | * Usage: savetransfer [-i|-o] OUTPUT_FILE PROGRAM [ARGS...] |
| 6 | * -i Save the input going to PROGRAM to the OUTPUT_FILE |
| 7 | * -o Save the output coming from PROGRAM to the OUTPUT_FILE |
| 8 | * |
| 9 | * If you want to capture the flow of data for an rsync command, use one of |
| 10 | * the following commands (the resulting files should be identical): |
| 11 | * |
| 12 | * rsync -av --rsh="savetransfer -i /tmp/to.server ssh" |
| 13 | * --rsync-path="savetransfer -i /tmp/from.client rsync" SOURCE DEST |
| 14 | * |
| 15 | * rsync -av --rsh="savetransfer -o /tmp/from.server ssh" |
| 16 | * --rsync-path="savetransfer -o /tmp/to.client rsync" SOURCE DEST |
| 17 | * |
| 18 | * Note that this program aborts after 30 seconds of inactivity, so you'll need |
| 19 | * to change it if that is not enough dead time for your transfer. Also, some |
| 20 | * of the above commands will not notice that the transfer is done (if we're |
| 21 | * saving the input to a PROGRAM and the PROGRAM goes away: we won't notice |
| 22 | * that it's gone unless more data comes in) -- when this happens it will delay |
| 23 | * at the end of the transfer until the timeout period expires. |
| 24 | */ |
| 25 | |
| 26 | #include "../rsync.h" |
| 27 | |
| 28 | #define TIMEOUT_SECONDS 30 |
| 29 | |
| 30 | #ifdef HAVE_SIGACTION |
| 31 | static struct sigaction sigact; |
| 32 | #endif |
| 33 | |
| 34 | void run_program(char **command); |
| 35 | |
| 36 | char buf[4096]; |
| 37 | int save_data_from_program = 0; |
| 38 | |
| 39 | int |
| 40 | main(int argc, char *argv[]) |
| 41 | { |
| 42 | int fd_file, len; |
| 43 | struct timeval tv; |
| 44 | fd_set fds; |
| 45 | |
| 46 | argv++; |
| 47 | if (--argc && argv[0][0] == '-') { |
| 48 | if (argv[0][1] == 'o') |
| 49 | save_data_from_program = 1; |
| 50 | else if (argv[0][1] == 'i') |
| 51 | save_data_from_program = 0; |
| 52 | else { |
| 53 | fprintf(stderr, "Unknown option: %s\n", argv[0]); |
| 54 | exit(1); |
| 55 | } |
| 56 | argv++; |
| 57 | argc--; |
| 58 | } |
| 59 | if (argc < 2) { |
| 60 | fprintf(stderr, "Usage: savetransfer [-i|-o] OUTPUT_FILE PROGRAM [ARGS...]\n"); |
| 61 | fprintf(stderr, "-i Save the input going to PROGRAM to the OUTPUT_FILE\n"); |
| 62 | fprintf(stderr, "-o Save the output coming from PROGRAM to the OUTPUT_FILE\n"); |
| 63 | exit(1); |
| 64 | } |
| 65 | if ((fd_file = open(*argv, O_WRONLY|O_TRUNC|O_CREAT|O_BINARY, 0644)) < 0) { |
| 66 | fprintf(stderr, "Unable to write to `%s': %s\n", *argv, strerror(errno)); |
| 67 | exit(1); |
| 68 | } |
| 69 | set_blocking(fd_file); |
| 70 | |
| 71 | SIGACTION(SIGPIPE, SIG_IGN); |
| 72 | |
| 73 | run_program(argv + 1); |
| 74 | |
| 75 | #if defined HAVE_SETMODE && O_BINARY |
| 76 | setmode(STDIN_FILENO, O_BINARY); |
| 77 | setmode(STDOUT_FILENO, O_BINARY); |
| 78 | #endif |
| 79 | set_nonblocking(STDIN_FILENO); |
| 80 | set_blocking(STDOUT_FILENO); |
| 81 | |
| 82 | while (1) { |
| 83 | FD_ZERO(&fds); |
| 84 | FD_SET(STDIN_FILENO, &fds); |
| 85 | tv.tv_sec = TIMEOUT_SECONDS; |
| 86 | tv.tv_usec = 0; |
| 87 | if (!select(STDIN_FILENO+1, &fds, NULL, NULL, &tv)) |
| 88 | break; |
| 89 | if (!FD_ISSET(STDIN_FILENO, &fds)) |
| 90 | break; |
| 91 | if ((len = read(STDIN_FILENO, buf, sizeof buf)) <= 0) |
| 92 | break; |
| 93 | if (write(STDOUT_FILENO, buf, len) != len) { |
| 94 | fprintf(stderr, "Failed to write data to stdout: %s\n", strerror(errno)); |
| 95 | exit(1); |
| 96 | } |
| 97 | if (write(fd_file, buf, len) != len) { |
| 98 | fprintf(stderr, "Failed to write data to fd_file: %s\n", strerror(errno)); |
| 99 | exit(1); |
| 100 | } |
| 101 | } |
| 102 | return 0; |
| 103 | } |
| 104 | |
| 105 | void |
| 106 | run_program(char **command) |
| 107 | { |
| 108 | int pipe_fds[2], ret; |
| 109 | pid_t pid; |
| 110 | |
| 111 | if (pipe(pipe_fds) < 0) { |
| 112 | fprintf(stderr, "pipe failed: %s\n", strerror(errno)); |
| 113 | exit(1); |
| 114 | } |
| 115 | |
| 116 | if ((pid = fork()) < 0) { |
| 117 | fprintf(stderr, "fork failed: %s\n", strerror(errno)); |
| 118 | exit(1); |
| 119 | } |
| 120 | |
| 121 | if (pid == 0) { |
| 122 | if (save_data_from_program) |
| 123 | ret = dup2(pipe_fds[1], STDOUT_FILENO); |
| 124 | else |
| 125 | ret = dup2(pipe_fds[0], STDIN_FILENO); |
| 126 | if (ret < 0) { |
| 127 | fprintf(stderr, "Failed to dup (in child): %s\n", strerror(errno)); |
| 128 | exit(1); |
| 129 | } |
| 130 | close(pipe_fds[0]); |
| 131 | close(pipe_fds[1]); |
| 132 | set_blocking(STDIN_FILENO); |
| 133 | set_blocking(STDOUT_FILENO); |
| 134 | execvp(command[0], command); |
| 135 | fprintf(stderr, "Failed to exec %s: %s\n", command[0], strerror(errno)); |
| 136 | exit(1); |
| 137 | } |
| 138 | |
| 139 | if (save_data_from_program) |
| 140 | ret = dup2(pipe_fds[0], STDIN_FILENO); |
| 141 | else |
| 142 | ret = dup2(pipe_fds[1], STDOUT_FILENO); |
| 143 | if (ret < 0) { |
| 144 | fprintf(stderr, "Failed to dup (in parent): %s\n", strerror(errno)); |
| 145 | exit(1); |
| 146 | } |
| 147 | close(pipe_fds[0]); |
| 148 | close(pipe_fds[1]); |
| 149 | } |
| 150 | |
| 151 | void |
| 152 | set_nonblocking(int fd) |
| 153 | { |
| 154 | int val; |
| 155 | |
| 156 | if ((val = fcntl(fd, F_GETFL, 0)) == -1) |
| 157 | return; |
| 158 | if (!(val & NONBLOCK_FLAG)) { |
| 159 | val |= NONBLOCK_FLAG; |
| 160 | fcntl(fd, F_SETFL, val); |
| 161 | } |
| 162 | } |
| 163 | |
| 164 | void |
| 165 | set_blocking(int fd) |
| 166 | { |
| 167 | int val; |
| 168 | |
| 169 | if ((val = fcntl(fd, F_GETFL, 0)) < 0) |
| 170 | return; |
| 171 | if (val & NONBLOCK_FLAG) { |
| 172 | val &= ~NONBLOCK_FLAG; |
| 173 | fcntl(fd, F_SETFL, val); |
| 174 | } |
| 175 | } |