X-Git-Url: http://git.annexia.org/?p=libguestfs.git;a=blobdiff_plain;f=src%2Flaunch.c;h=56aa288b16665c6901c77c9960fef14e4a14cd39;hp=ecc0464a88edfa09d20a3b6cc964d6c727d9bdd4;hb=5d7dc0dfb65f367dab3560ee23e404fe21373f45;hpb=607aa95de927b5b8e4b212655c71bf21acbba372 diff --git a/src/launch.c b/src/launch.c index ecc0464..56aa288 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" @@ -75,6 +76,34 @@ static int64_t timeval_diff (const struct timeval *x, const struct timeval *y); 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) @@ -487,21 +516,30 @@ launch_appliance (guestfs_h *g) if (qemu_supports (g, "-nodefconfig")) add_cmdline (g, "-nodefconfig"); - /* qemu sometimes needs this option to enable hardware - * virtualization, but some versions of 'qemu-kvm' will use KVM - * regardless (even where this option appears in the help text). - * It is rumoured that there are versions of qemu where supplying - * this option when hardware virtualization is not available will - * cause qemu to fail, so we we have to check at least that - * /dev/kvm is openable. That's not reliable, since /dev/kvm - * might be openable by qemu but not by us (think: SELinux) in - * which case the user would not get hardware virtualization, - * although at least shouldn't fail. A giant clusterfuck with the - * qemu command line, again. + /* The qemu -machine option (added 2010-12) is a bit more sane + * since it falls back through various different acceleration + * modes, so try that first (thanks Markus Armbruster). */ - if (qemu_supports (g, "-enable-kvm") && - is_openable (g, "/dev/kvm", O_RDWR)) - add_cmdline (g, "-enable-kvm"); + if (qemu_supports (g, "-machine")) { + add_cmdline (g, "-machine"); + add_cmdline (g, "accel=kvm:tcg"); + } else { + /* qemu sometimes needs this option to enable hardware + * virtualization, but some versions of 'qemu-kvm' will use KVM + * regardless (even where this option appears in the help text). + * It is rumoured that there are versions of qemu where supplying + * this option when hardware virtualization is not available will + * cause qemu to fail, so we we have to check at least that + * /dev/kvm is openable. That's not reliable, since /dev/kvm + * might be openable by qemu but not by us (think: SELinux) in + * which case the user would not get hardware virtualization, + * although at least shouldn't fail. A giant clusterfuck with the + * qemu command line, again. + */ + if (qemu_supports (g, "-enable-kvm") && + is_openable (g, "/dev/kvm", O_RDWR)) + add_cmdline (g, "-enable-kvm"); + } /* Newer versions of qemu (from around 2009/12) changed the * behaviour of monitors so that an implicit '-monitor stdio' is @@ -616,17 +654,27 @@ launch_appliance (guestfs_h *g) 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; @@ -634,12 +682,9 @@ 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 + /* Put qemu in a new process group. */ + if (g->pgroup) + setpgid (0, 0); setenv ("LC_ALL", "C", 1); @@ -668,6 +713,14 @@ 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 */ @@ -1106,6 +1159,20 @@ 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)