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-rw-r--r--misc/logsave.c334
1 files changed, 334 insertions, 0 deletions
diff --git a/misc/logsave.c b/misc/logsave.c
new file mode 100644
index 0000000..96b6d8e
--- /dev/null
+++ b/misc/logsave.c
@@ -0,0 +1,334 @@
+/*
+ * logsave.c --- A program which saves the output of a program until
+ * /var/log is mounted.
+ *
+ * Copyright (C) 2003 Theodore Ts'o.
+ *
+ * %Begin-Header%
+ * This file may be redistributed under the terms of the GNU Public
+ * License.
+ * %End-Header%
+ */
+
+#define _XOPEN_SOURCE 600 /* for inclusion of sa_handler in Solaris */
+
+#include "config.h"
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <string.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <fcntl.h>
+#include <time.h>
+#include <errno.h>
+#ifdef HAVE_SIGNAL_H
+#include <signal.h>
+#endif
+#ifdef HAVE_GETOPT_H
+#include <getopt.h>
+#else
+extern char *optarg;
+extern int optind;
+#endif
+
+static int outfd = -1;
+static int outbufsize = 0;
+static void *outbuf = 0;
+static int verbose = 0;
+static int do_skip = 0;
+static int skip_mode = 0;
+static pid_t child_pid = -1;
+
+static void usage(char *progname)
+{
+ printf("Usage: %s [-asv] logfile program\n", progname);
+ exit(1);
+}
+
+#define SEND_LOG 0x01
+#define SEND_CONSOLE 0x02
+#define SEND_BOTH 0x03
+
+/*
+ * Helper function that does the right thing if write returns a
+ * partial write, or an EAGAIN/EINTR error.
+ */
+static int write_all(int fd, const char *buf, size_t count)
+{
+ ssize_t ret;
+ int c = 0;
+
+ while (count > 0) {
+ ret = write(fd, buf, count);
+ if (ret < 0) {
+ if ((errno == EAGAIN) || (errno == EINTR))
+ continue;
+ return -1;
+ }
+ count -= ret;
+ buf += ret;
+ c += ret;
+ }
+ return c;
+}
+
+static void send_output(const char *buffer, int c, int flag)
+{
+ const char *cp;
+ char *n;
+ int cnt, d, del;
+
+ if (c == 0)
+ c = strlen(buffer);
+
+ if (flag & SEND_CONSOLE) {
+ cnt = c;
+ cp = buffer;
+ while (cnt) {
+ del = 0;
+ for (d=0; d < cnt; d++) {
+ if (skip_mode &&
+ (cp[d] == '\001' || cp[d] == '\002')) {
+ del = 1;
+ break;
+ }
+ }
+ write_all(1, cp, d);
+ if (del)
+ d++;
+ cnt -= d;
+ cp += d;
+ }
+ }
+ if (!(flag & SEND_LOG))
+ return;
+ if (outfd > 0)
+ write_all(outfd, buffer, c);
+ else {
+ n = realloc(outbuf, outbufsize + c);
+ if (n) {
+ outbuf = n;
+ memcpy(((char *)outbuf)+outbufsize, buffer, c);
+ outbufsize += c;
+ }
+ }
+}
+
+static int do_read(int fd)
+{
+ int c;
+ char buffer[4096], *cp, *sep;
+
+ c = read(fd, buffer, sizeof(buffer)-1);
+ if (c <= 0)
+ return c;
+ if (do_skip) {
+ send_output(buffer, c, SEND_CONSOLE);
+ buffer[c] = 0;
+ cp = buffer;
+ while (*cp) {
+ if (skip_mode) {
+ cp = strchr(cp, '\002');
+ if (!cp)
+ return 0;
+ cp++;
+ skip_mode = 0;
+ continue;
+ }
+ sep = strchr(cp, '\001');
+ if (sep)
+ *sep = 0;
+ send_output(cp, 0, SEND_LOG);
+ if (sep) {
+ cp = sep + 1;
+ skip_mode = 1;
+ } else
+ break;
+ }
+ } else
+ send_output(buffer, c, SEND_BOTH);
+ return c;
+}
+
+static void signal_term(int sig)
+{
+ if (child_pid > 0)
+ kill(child_pid, sig);
+}
+
+static int run_program(char **argv)
+{
+ int fds[2];
+ int status, rc, pid;
+ char buffer[80];
+#ifdef HAVE_SIGNAL_H
+ struct sigaction sa;
+#endif
+
+ if (pipe(fds) < 0) {
+ perror("pipe");
+ exit(1);
+ }
+
+#ifdef HAVE_SIGNAL_H
+ memset(&sa, 0, sizeof(struct sigaction));
+ sa.sa_handler = signal_term;
+ sigaction(SIGINT, &sa, 0);
+ sigaction(SIGTERM, &sa, 0);
+#ifdef SA_RESTART
+ sa.sa_flags = SA_RESTART;
+#endif
+#endif
+
+ pid = fork();
+ if (pid < 0) {
+ perror("vfork");
+ exit(1);
+ }
+ if (pid == 0) {
+ dup2(fds[1],1); /* fds[1] replaces stdout */
+ dup2(fds[1],2); /* fds[1] replaces stderr */
+ close(fds[0]); /* don't need this here */
+ close(fds[1]);
+
+ execvp(argv[0], argv);
+ perror(argv[0]);
+ exit(1);
+ }
+ child_pid = pid;
+ close(fds[1]);
+
+ while (!(waitpid(pid, &status, WNOHANG ))) {
+ do_read(fds[0]);
+ }
+ child_pid = -1;
+ do_read(fds[0]);
+ close(fds[0]);
+
+ if ( WIFEXITED(status) ) {
+ rc = WEXITSTATUS(status);
+ if (rc) {
+ send_output(argv[0], 0, SEND_BOTH);
+ sprintf(buffer, " exited with status code %d\n", rc);
+ send_output(buffer, 0, SEND_BOTH);
+ }
+ } else {
+ if (WIFSIGNALED(status)) {
+ send_output(argv[0], 0, SEND_BOTH);
+ sprintf(buffer, "died with signal %d\n",
+ WTERMSIG(status));
+ send_output(buffer, 0, SEND_BOTH);
+ return 1;
+ }
+ rc = 0;
+ }
+ return rc;
+}
+
+static int copy_from_stdin(void)
+{
+ int c, bad_read = 0;
+
+ while (1) {
+ c = do_read(0);
+ if ((c == 0 ) ||
+ ((c < 0) && ((errno == EAGAIN) || (errno == EINTR)))) {
+ if (bad_read++ > 3)
+ break;
+ continue;
+ }
+ if (c < 0) {
+ perror("read");
+ exit(1);
+ }
+ bad_read = 0;
+ }
+ return 0;
+}
+
+
+
+int main(int argc, char **argv)
+{
+ int c, pid, rc;
+ char *outfn, **cpp;
+ int openflags = O_CREAT|O_WRONLY|O_TRUNC;
+ int send_flag = SEND_LOG;
+ int do_stdin;
+ time_t t;
+
+ while ((c = getopt(argc, argv, "+asv")) != EOF) {
+ switch (c) {
+ case 'a':
+ openflags &= ~O_TRUNC;
+ openflags |= O_APPEND;
+ break;
+ case 's':
+ do_skip = 1;
+ break;
+ case 'v':
+ verbose++;
+ send_flag |= SEND_CONSOLE;
+ break;
+ }
+ }
+ if (optind == argc || optind+1 == argc)
+ usage(argv[0]);
+ outfn = argv[optind];
+ optind++;
+ argv += optind;
+ argc -= optind;
+
+ outfd = open(outfn, openflags, 0644);
+ do_stdin = !strcmp(argv[0], "-");
+
+ send_output("Log of ", 0, send_flag);
+ if (do_stdin)
+ send_output("stdin", 0, send_flag);
+ else {
+ for (cpp = argv; *cpp; cpp++) {
+ send_output(*cpp, 0, send_flag);
+ send_output(" ", 0, send_flag);
+ }
+ }
+ send_output("\n", 0, send_flag);
+ t = time(0);
+ send_output(ctime(&t), 0, send_flag);
+ send_output("\n", 0, send_flag);
+
+ if (do_stdin)
+ rc = copy_from_stdin();
+ else
+ rc = run_program(argv);
+
+ send_output("\n", 0, send_flag);
+ t = time(0);
+ send_output(ctime(&t), 0, send_flag);
+ send_output("----------------\n", 0, send_flag);
+
+ if (outbuf) {
+ pid = fork();
+ if (pid < 0) {
+ perror("fork");
+ exit(1);
+ }
+ if (pid) {
+ if (verbose)
+ printf("Backgrounding to save %s later\n",
+ outfn);
+ exit(rc);
+ }
+ setsid(); /* To avoid getting killed by init */
+ while (outfd < 0) {
+ outfd = open(outfn, openflags, 0644);
+ sleep(1);
+ }
+ write_all(outfd, outbuf, outbufsize);
+ free(outbuf);
+ }
+ if (outfd >= 0)
+ close(outfd);
+
+ exit(rc);
+}