From ada45c785fc7b0cbe0adb9cbf641943410f4953f Mon Sep 17 00:00:00 2001 From: Lennart Poettering Date: Sat, 27 Oct 2012 01:19:47 +0200 Subject: coredumpctl: add 'gdb' verb to start gdb right-away on a collected coredump --- man/systemd-coredumpctl.xml | 13 +++- src/journal/coredumpctl.c | 142 ++++++++++++++++++++++++++++++++++++++++---- 2 files changed, 141 insertions(+), 14 deletions(-) diff --git a/man/systemd-coredumpctl.xml b/man/systemd-coredumpctl.xml index 378d40fa13..bbb4214213 100644 --- a/man/systemd-coredumpctl.xml +++ b/man/systemd-coredumpctl.xml @@ -121,6 +121,16 @@ + + + gdb + + Invoke the GNU + debugger on the last coredump matching + specified characteristics. + + + @@ -179,7 +189,8 @@ See Also - systemd-journald.service8 + systemd-journald.service8, + gdb1 diff --git a/src/journal/coredumpctl.c b/src/journal/coredumpctl.c index 7cf6b4590b..5b494e340b 100644 --- a/src/journal/coredumpctl.c +++ b/src/journal/coredumpctl.c @@ -22,6 +22,8 @@ #include #include #include +#include +#include #include @@ -36,6 +38,7 @@ static enum { ACTION_NONE, ACTION_LIST, ACTION_DUMP, + ACTION_GDB, } arg_action = ACTION_LIST; static Set *matches = NULL; @@ -191,6 +194,8 @@ static int parse_argv(int argc, char *argv[]) { arg_action = ACTION_LIST; else if (streq(cmd, "dump")) arg_action = ACTION_DUMP; + else if (streq(cmd, "gdb")) + arg_action = ACTION_GDB; else { log_error("Unknown action '%s'", cmd); return -EINVAL; @@ -304,13 +309,9 @@ static int dump_list(sd_journal *j) { return 0; } -static int dump_core(sd_journal* j) { - const char *data; - size_t len, ret; +static int focus(sd_journal *j) { int r; - assert(j); - r = sd_journal_seek_tail(j); if (r == 0) r = sd_journal_previous(j); @@ -318,17 +319,23 @@ static int dump_core(sd_journal* j) { log_error("Failed to search journal: %s", strerror(-r)); return r; } - if (r == 0) { log_error("No match found"); return -ESRCH; } + return r; +} - r = sd_journal_get_data(j, "COREDUMP", (const void**) &data, &len); - if (r != 0) { - log_error("retrieve COREDUMP field: %s", strerror(-r)); +static int dump_core(sd_journal* j) { + const void *data; + size_t len, ret; + int r; + + assert(j); + + r = focus(j); + if (r < 0) return r; - } print_entry(output ? stdout : stderr, j, false); @@ -337,9 +344,17 @@ static int dump_core(sd_journal* j) { return -ENOTTY; } + r = sd_journal_get_data(j, "COREDUMP", (const void**) &data, &len); + if (r < 0) { + log_error("Failed to retrieve COREDUMP field: %s", strerror(-r)); + return r; + } + assert(len >= 9); + data = (const uint8_t*) data + 9; + len -= 9; - ret = fwrite(data+9, len-9, 1, output ? output : stdout); + ret = fwrite(data, len, 1, output ? output : stdout); if (ret != 1) { log_error("dumping coredump: %m (%zu)", ret); return -errno; @@ -352,6 +367,100 @@ static int dump_core(sd_journal* j) { return 0; } +static int run_gdb(sd_journal *j) { + char path[] = "/var/tmp/coredump-XXXXXX"; + const void *data; + size_t len; + ssize_t sz; + pid_t pid; + _cleanup_free_ char *exe = NULL; + int r; + _cleanup_close_ int fd = -1; + siginfo_t st; + + assert(j); + + r = focus(j); + if (r < 0) + return r; + + print_entry(stdout, j, false); + + r = sd_journal_get_data(j, "COREDUMP_EXE", (const void**) &data, &len); + if (r < 0) { + log_error("Failed to retrieve COREDUMP_EXE field: %s", strerror(-r)); + return r; + } + + assert(len >= 13); + data = (const uint8_t*) data + 13; + len -= 13; + + exe = strndup(data, len); + if (!exe) + return log_oom(); + + if (endswith(exe, " (deleted)")) { + log_error("Binary already deleted."); + return -ENOENT; + } + + r = sd_journal_get_data(j, "COREDUMP", (const void**) &data, &len); + if (r < 0) { + log_error("Failed to retrieve COREDUMP field: %s", strerror(-r)); + return r; + } + + assert(len >= 9); + data = (const uint8_t*) data + 9; + len -= 9; + + fd = mkostemp(path, O_WRONLY); + if (fd < 0) { + log_error("Failed to create temporary file: %m"); + return -errno; + } + + sz = write(fd, data, len); + if (sz < 0) { + log_error("Failed to write temporary file: %s", strerror(errno)); + r = -errno; + goto finish; + } + if (sz != (ssize_t) len) { + log_error("Short write to temporary file."); + r = -EIO; + goto finish; + } + + close_nointr_nofail(fd); + fd = -1; + + pid = fork(); + if (pid < 0) { + log_error("Failed to fork(): %m"); + r = -errno; + goto finish; + } + if (pid == 0) { + execlp("gdb", "gdb", exe, path, NULL); + log_error("Failed to invoke gdb: %m"); + _exit(1); + } + + r = wait_for_terminate(pid, &st); + if (r < 0) { + log_error("Failed to wait for gdb: %m"); + goto finish; + } + + r = st.si_code == CLD_EXITED ? st.si_status : 255; + +finish: + unlink(path); + return r; +} + int main(int argc, char *argv[]) { sd_journal *j = NULL; const char* match; @@ -387,16 +496,23 @@ int main(int argc, char *argv[]) { } switch(arg_action) { + case ACTION_LIST: if (!arg_no_pager) pager_open(); r = dump_list(j); break; + case ACTION_DUMP: r = dump_core(j); break; - case ACTION_NONE: + + case ACTION_GDB: + r = run_gdb(j); + break; + + default: assert_not_reached("Shouldn't be here"); } @@ -411,5 +527,5 @@ end: if (output) fclose(output); - return r == 0 ? EXIT_SUCCESS : EXIT_FAILURE; + return r >= 0 ? r : EXIT_FAILURE; } -- cgit v1.2.3-54-g00ecf