X-Git-Url: http://git.annexia.org/?a=blobdiff_plain;f=src%2Flaunch.c;h=03ad39b4b3b61df873ea9d13fa1740bde8efd1ba;hb=eb209a3664906257b3dc87b6f7b04ff54e0d1288;hp=0b15ce98d79fac55032a7e93788f62d0011e8c34;hpb=64841fe8957f798df12a38bd81843c7011f2c278;p=libguestfs.git diff --git a/src/launch.c b/src/launch.c index 0b15ce9..03ad39b 100644 --- a/src/launch.c +++ b/src/launch.c @@ -63,6 +63,7 @@ #include #include "c-ctype.h" +#include "ignore-value.h" #include "glthread/lock.h" #include "guestfs.h" @@ -72,9 +73,38 @@ static int launch_appliance (guestfs_h *g); static int64_t timeval_diff (const struct timeval *x, const struct timeval *y); +static void print_qemu_command_line (guestfs_h *g, char **argv); static int connect_unix_socket (guestfs_h *g, const char *sock); static int qemu_supports (guestfs_h *g, const char *option); +#if 0 +static int qemu_supports_re (guestfs_h *g, const pcre *option_regex); + +static void compile_regexps (void) __attribute__((constructor)); +static void free_regexps (void) __attribute__((destructor)); + +static void +compile_regexps (void) +{ + const char *err; + int offset; + +#define COMPILE(re,pattern,options) \ + do { \ + re = pcre_compile ((pattern), (options), &err, &offset, NULL); \ + if (re == NULL) { \ + ignore_value (write (2, err, strlen (err))); \ + abort (); \ + } \ + } while (0) +} + +static void +free_regexps (void) +{ +} +#endif + /* Add a string to the current command line. */ static void incr_cmdline_size (guestfs_h *g) @@ -621,21 +651,28 @@ launch_appliance (guestfs_h *g) incr_cmdline_size (g); g->cmdline[g->cmdline_size-1] = NULL; - if (g->verbose) - guestfs___print_timestamped_argv (g, (const char **)g->cmdline); - if (!g->direct) { - /* Set up stdin, stdout. */ + /* Set up stdin, stdout, stderr. */ close (0); close (1); close (wfd[1]); close (rfd[0]); + /* Stdin. */ if (dup (wfd[0]) == -1) { dup_failed: perror ("dup failed"); _exit (EXIT_FAILURE); } + /* Stdout. */ + if (dup (rfd[1]) == -1) + goto dup_failed; + + /* Particularly since qemu 0.15, qemu spews all sorts of debug + * information on stderr. It is useful to both capture this and + * not confuse casual users, so send stderr to the pipe as well. + */ + close (2); if (dup (rfd[1]) == -1) goto dup_failed; @@ -643,12 +680,13 @@ launch_appliance (guestfs_h *g) close (rfd[1]); } -#if 0 - /* Set up a new process group, so we can signal this process - * and all subprocesses (eg. if qemu is really a shell script). - */ - setpgid (0, 0); -#endif + /* Dump the command line (after setting up stderr above). */ + if (g->verbose) + print_qemu_command_line (g, g->cmdline); + + /* Put qemu in a new process group. */ + if (g->pgroup) + setpgid (0, 0); setenv ("LC_ALL", "C", 1); @@ -677,8 +715,16 @@ launch_appliance (guestfs_h *g) pid_t qemu_pid = g->pid; pid_t parent_pid = getppid (); + /* It would be nice to be able to put this in the same process + * group as qemu (ie. setpgid (0, qemu_pid)). However this is + * not possible because we don't have any guarantee here that + * the qemu process has started yet. + */ + if (g->pgroup) + setpgid (0, 0); + /* Writing to argv is hideously complicated and error prone. See: - * http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/utils/misc/ps_status.c?rev=1.33.2.1;content-type=text%2Fplain + * http://git.postgresql.org/gitweb/?p=postgresql.git;a=blob;f=src/backend/utils/misc/ps_status.c;hb=HEAD */ /* Loop around waiting for one or both of the other processes to @@ -958,47 +1004,9 @@ timeval_diff (const struct timeval *x, const struct timeval *y) return msec; } -void -guestfs___print_timestamped_argv (guestfs_h *g, const char * argv[]) -{ - int i = 0; - int needs_quote; - char *buf = NULL; - size_t len; - FILE *fp; - - fp = open_memstream (&buf, &len); - if (fp == NULL) { - warning (g, "open_memstream: %m"); - return; - } - - struct timeval tv; - gettimeofday (&tv, NULL); - fprintf (fp, "[%05" PRIi64 "ms] ", timeval_diff (&g->launch_t, &tv)); - - while (argv[i]) { - if (argv[i][0] == '-') /* -option starts a new line */ - fprintf (fp, " \\\n "); - - if (i > 0) fputc (' ', fp); - - /* Does it need shell quoting? This only deals with simple cases. */ - needs_quote = strcspn (argv[i], " ") != strlen (argv[i]); - - if (needs_quote) fputc ('\'', fp); - fprintf (fp, "%s", argv[i]); - if (needs_quote) fputc ('\'', fp); - i++; - } - - fclose (fp); - - debug (g, "%s", buf); - - free (buf); -} - +/* Note that since this calls 'debug' it should only be called + * from the parent process. + */ void guestfs___print_timestamped_message (guestfs_h *g, const char *fs, ...) { @@ -1020,6 +1028,37 @@ guestfs___print_timestamped_message (guestfs_h *g, const char *fs, ...) free (msg); } +/* This is called from the forked subprocess just before qemu runs, so + * it can just print the message straight to stderr, where it will be + * picked up and funnelled through the usual appliance event API. + */ +static void +print_qemu_command_line (guestfs_h *g, char **argv) +{ + int i = 0; + int needs_quote; + + struct timeval tv; + gettimeofday (&tv, NULL); + fprintf (stderr, "[%05" PRIi64 "ms] ", timeval_diff (&g->launch_t, &tv)); + + while (argv[i]) { + if (argv[i][0] == '-') /* -option starts a new line */ + fprintf (stderr, " \\\n "); + + if (i > 0) fputc (' ', stderr); + + /* Does it need shell quoting? This only deals with simple cases. */ + needs_quote = strcspn (argv[i], " ") != strlen (argv[i]); + + if (needs_quote) fputc ('\'', stderr); + fprintf (stderr, "%s", argv[i]); + if (needs_quote) fputc ('\'', stderr); + i++; + } +} + +static int test_qemu_cmd (guestfs_h *g, const char *cmd, char **ret); static int read_all (guestfs_h *g, FILE *fp, char **ret); /* Test qemu binary (or wrapper) runs, and do 'qemu -help' and @@ -1032,38 +1071,49 @@ test_qemu (guestfs_h *g) char cmd[1024]; FILE *fp; + free (g->qemu_help); + g->qemu_help = NULL; + free (g->qemu_version); + g->qemu_version = NULL; + snprintf (cmd, sizeof cmd, "LC_ALL=C '%s' -nographic -help", g->qemu); - fp = popen (cmd, "r"); /* qemu -help should always work (qemu -version OTOH wasn't * supported by qemu 0.9). If this command doesn't work then it * probably indicates that the qemu binary is missing. */ - if (!fp) { - /* XXX This error is never printed, even if the qemu binary - * doesn't exist. Why? - */ - error: - perrorf (g, _("%s: command failed: If qemu is located on a non-standard path, try setting the LIBGUESTFS_QEMU environment variable."), cmd); + if (test_qemu_cmd (g, cmd, &g->qemu_help) == -1) { + error (g, _("command failed: %s\n\nIf qemu is located on a non-standard path, try setting the LIBGUESTFS_QEMU\nenvironment variable. There may also be errors printed above."), + cmd); return -1; } - if (read_all (g, fp, &g->qemu_help) == -1) - goto error; - - if (pclose (fp) == -1) - goto error; - snprintf (cmd, sizeof cmd, "LC_ALL=C '%s' -nographic -version 2>/dev/null", g->qemu); + /* Intentionally ignore errors from qemu -version. */ + ignore_value (test_qemu_cmd (g, cmd, &g->qemu_version)); + + return 0; +} + +static int +test_qemu_cmd (guestfs_h *g, const char *cmd, char **ret) +{ + FILE *fp; + fp = popen (cmd, "r"); - if (fp) { - /* Intentionally ignore errors. */ - read_all (g, fp, &g->qemu_version); + if (fp == NULL) + return -1; + + if (read_all (g, fp, ret) == -1) { pclose (fp); + return -1; } + if (pclose (fp) != 0) + return -1; + return 0; } @@ -1115,6 +1165,20 @@ qemu_supports (guestfs_h *g, const char *option) return strstr (g->qemu_help, option) != NULL; } +#if 0 +/* As above but using a regex instead of a fixed string. */ +static int +qemu_supports_re (guestfs_h *g, const pcre *option_regex) +{ + if (!g->qemu_help) { + if (test_qemu (g) == -1) + return -1; + } + + return match (g, g->qemu_help, option_regex); +} +#endif + /* Check if a file can be opened. */ static int is_openable (guestfs_h *g, const char *path, int flags)