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-rw-r--r--support/savetransfer.c175
1 files changed, 175 insertions, 0 deletions
diff --git a/support/savetransfer.c b/support/savetransfer.c
new file mode 100644
index 0000000..808a6f2
--- /dev/null
+++ b/support/savetransfer.c
@@ -0,0 +1,175 @@
+/* This program can record the stream of data flowing to or from a program.
+ * This allows it to be used to check that rsync's data that is flowing
+ * through a remote shell is not being corrupted (for example).
+ *
+ * Usage: savetransfer [-i|-o] OUTPUT_FILE PROGRAM [ARGS...]
+ * -i Save the input going to PROGRAM to the OUTPUT_FILE
+ * -o Save the output coming from PROGRAM to the OUTPUT_FILE
+ *
+ * If you want to capture the flow of data for an rsync command, use one of
+ * the following commands (the resulting files should be identical):
+ *
+ * rsync -av --rsh="savetransfer -i /tmp/to.server ssh"
+ * --rsync-path="savetransfer -i /tmp/from.client rsync" SOURCE DEST
+ *
+ * rsync -av --rsh="savetransfer -o /tmp/from.server ssh"
+ * --rsync-path="savetransfer -o /tmp/to.client rsync" SOURCE DEST
+ *
+ * Note that this program aborts after 30 seconds of inactivity, so you'll need
+ * to change it if that is not enough dead time for your transfer. Also, some
+ * of the above commands will not notice that the transfer is done (if we're
+ * saving the input to a PROGRAM and the PROGRAM goes away: we won't notice
+ * that it's gone unless more data comes in) -- when this happens it will delay
+ * at the end of the transfer until the timeout period expires.
+ */
+
+#include "../rsync.h"
+
+#define TIMEOUT_SECONDS 30
+
+#ifdef HAVE_SIGACTION
+static struct sigaction sigact;
+#endif
+
+void run_program(char **command);
+
+char buf[4096];
+int save_data_from_program = 0;
+
+int
+main(int argc, char *argv[])
+{
+ int fd_file, len;
+ struct timeval tv;
+ fd_set fds;
+
+ argv++;
+ if (--argc && argv[0][0] == '-') {
+ if (argv[0][1] == 'o')
+ save_data_from_program = 1;
+ else if (argv[0][1] == 'i')
+ save_data_from_program = 0;
+ else {
+ fprintf(stderr, "Unknown option: %s\n", argv[0]);
+ exit(1);
+ }
+ argv++;
+ argc--;
+ }
+ if (argc < 2) {
+ fprintf(stderr, "Usage: savetransfer [-i|-o] OUTPUT_FILE PROGRAM [ARGS...]\n");
+ fprintf(stderr, "-i Save the input going to PROGRAM to the OUTPUT_FILE\n");
+ fprintf(stderr, "-o Save the output coming from PROGRAM to the OUTPUT_FILE\n");
+ exit(1);
+ }
+ if ((fd_file = open(*argv, O_WRONLY|O_TRUNC|O_CREAT|O_BINARY, 0644)) < 0) {
+ fprintf(stderr, "Unable to write to `%s': %s\n", *argv, strerror(errno));
+ exit(1);
+ }
+ set_blocking(fd_file);
+
+ SIGACTION(SIGPIPE, SIG_IGN);
+
+ run_program(argv + 1);
+
+#if defined HAVE_SETMODE && O_BINARY
+ setmode(STDIN_FILENO, O_BINARY);
+ setmode(STDOUT_FILENO, O_BINARY);
+#endif
+ set_nonblocking(STDIN_FILENO);
+ set_blocking(STDOUT_FILENO);
+
+ while (1) {
+ FD_ZERO(&fds);
+ FD_SET(STDIN_FILENO, &fds);
+ tv.tv_sec = TIMEOUT_SECONDS;
+ tv.tv_usec = 0;
+ if (!select(STDIN_FILENO+1, &fds, NULL, NULL, &tv))
+ break;
+ if (!FD_ISSET(STDIN_FILENO, &fds))
+ break;
+ if ((len = read(STDIN_FILENO, buf, sizeof buf)) <= 0)
+ break;
+ if (write(STDOUT_FILENO, buf, len) != len) {
+ fprintf(stderr, "Failed to write data to stdout: %s\n", strerror(errno));
+ exit(1);
+ }
+ if (write(fd_file, buf, len) != len) {
+ fprintf(stderr, "Failed to write data to fd_file: %s\n", strerror(errno));
+ exit(1);
+ }
+ }
+ return 0;
+}
+
+void
+run_program(char **command)
+{
+ int pipe_fds[2], ret;
+ pid_t pid;
+
+ if (pipe(pipe_fds) < 0) {
+ fprintf(stderr, "pipe failed: %s\n", strerror(errno));
+ exit(1);
+ }
+
+ if ((pid = fork()) < 0) {
+ fprintf(stderr, "fork failed: %s\n", strerror(errno));
+ exit(1);
+ }
+
+ if (pid == 0) {
+ if (save_data_from_program)
+ ret = dup2(pipe_fds[1], STDOUT_FILENO);
+ else
+ ret = dup2(pipe_fds[0], STDIN_FILENO);
+ if (ret < 0) {
+ fprintf(stderr, "Failed to dup (in child): %s\n", strerror(errno));
+ exit(1);
+ }
+ close(pipe_fds[0]);
+ close(pipe_fds[1]);
+ set_blocking(STDIN_FILENO);
+ set_blocking(STDOUT_FILENO);
+ execvp(command[0], command);
+ fprintf(stderr, "Failed to exec %s: %s\n", command[0], strerror(errno));
+ exit(1);
+ }
+
+ if (save_data_from_program)
+ ret = dup2(pipe_fds[0], STDIN_FILENO);
+ else
+ ret = dup2(pipe_fds[1], STDOUT_FILENO);
+ if (ret < 0) {
+ fprintf(stderr, "Failed to dup (in parent): %s\n", strerror(errno));
+ exit(1);
+ }
+ close(pipe_fds[0]);
+ close(pipe_fds[1]);
+}
+
+void
+set_nonblocking(int fd)
+{
+ int val;
+
+ if ((val = fcntl(fd, F_GETFL, 0)) == -1)
+ return;
+ if (!(val & NONBLOCK_FLAG)) {
+ val |= NONBLOCK_FLAG;
+ fcntl(fd, F_SETFL, val);
+ }
+}
+
+void
+set_blocking(int fd)
+{
+ int val;
+
+ if ((val = fcntl(fd, F_GETFL, 0)) < 0)
+ return;
+ if (val & NONBLOCK_FLAG) {
+ val &= ~NONBLOCK_FLAG;
+ fcntl(fd, F_SETFL, val);
+ }
+}