From c10fa84ada465d83bcbe0550ed512215036b4bea Mon Sep 17 00:00:00 2001 From: Richard Jones Date: Fri, 8 May 2009 15:19:51 +0100 Subject: [PATCH] Implement -command (to ignore errors) in guestfish, and allow recovery from qemu process failure. --- fish/alloc.c | 2 +- fish/fish.c | 36 ++++++++++++++++++++++++------------ fish/fish.h | 1 - guestfish.pod | 16 ++++++++++++++++ 4 files changed, 41 insertions(+), 14 deletions(-) diff --git a/fish/alloc.c b/fish/alloc.c index 594d0a5..9ef7b49 100644 --- a/fish/alloc.c +++ b/fish/alloc.c @@ -43,7 +43,7 @@ do_alloc (const char *cmd, int argc, char *argv[]) if (parse_size (argv[1], &size) == -1) return -1; - if (g_launched) { + if (!guestfs_is_config (g)) { fprintf (stderr, "can't allocate or add disks after launching\n"); return -1; } diff --git a/fish/fish.c b/fish/fish.c index 1309c68..fa34510 100644 --- a/fish/fish.c +++ b/fish/fish.c @@ -57,7 +57,6 @@ static void add_history_line (const char *); /* Currently open libguestfs handle. */ guestfs_h *g; -int g_launched = 0; int read_only = 0; int quit = 0; @@ -68,12 +67,11 @@ launch (guestfs_h *_g) { assert (_g == g); - if (!g_launched) { + if (guestfs_is_config (g)) { if (guestfs_launch (g) == -1) return -1; if (guestfs_wait_ready (g) == -1) return -1; - g_launched = 1; } return 0; } @@ -335,6 +333,8 @@ script (int prompt) char *p, *pend; char *argv[64]; int i, len; + int global_exit_on_error = !prompt; + int exit_on_error; if (prompt) printf ("\n" @@ -346,6 +346,8 @@ script (int prompt) "\n"); while (!quit) { + exit_on_error = global_exit_on_error; + buf = rl_gets (prompt); if (!buf) { quit = 1; @@ -353,6 +355,7 @@ script (int prompt) } /* Skip any initial whitespace before the command. */ + again: while (*buf && isspace (*buf)) buf++; @@ -366,7 +369,7 @@ script (int prompt) int r; r = system (buf+1); - if (!prompt) { + if (exit_on_error) { if (r == -1 || (WIFSIGNALED (r) && (WTERMSIG (r) == SIGINT || WTERMSIG (r) == SIGQUIT)) || @@ -376,6 +379,15 @@ script (int prompt) continue; } + /* If the next character is '-' allow the command to fail without + * exiting on error (just for this one command though). + */ + if (*buf == '-') { + exit_on_error = 0; + buf++; + goto again; + } + /* Get the command (cannot be quoted). */ len = strcspn (buf, " \t"); @@ -403,12 +415,12 @@ script (int prompt) len = strcspn (p, "\""); if (p[len] == '\0') { fprintf (stderr, "guestfish: unterminated double quote\n"); - if (!prompt) exit (1); + if (exit_on_error) exit (1); goto next_command; } if (p[len+1] && (p[len+1] != ' ' && p[len+1] != '\t')) { fprintf (stderr, "guestfish: command arguments not separated by whitespace\n"); - if (!prompt) exit (1); + if (exit_on_error) exit (1); goto next_command; } p[len] = '\0'; @@ -418,12 +430,12 @@ script (int prompt) len = strcspn (p, "'"); if (p[len] == '\0') { fprintf (stderr, "guestfish: unterminated single quote\n"); - if (!prompt) exit (1); + if (exit_on_error) exit (1); goto next_command; } if (p[len+1] && (p[len+1] != ' ' && p[len+1] != '\t')) { fprintf (stderr, "guestfish: command arguments not separated by whitespace\n"); - if (!prompt) exit (1); + if (exit_on_error) exit (1); goto next_command; } p[len] = '\0'; @@ -440,12 +452,12 @@ script (int prompt) } if (c != 0) { fprintf (stderr, "guestfish: unterminated \"[...]\" sequence\n"); - if (!prompt) exit (1); + if (exit_on_error) exit (1); goto next_command; } if (*pend && (*pend != ' ' && *pend != '\t')) { fprintf (stderr, "guestfish: command arguments not separated by whitespace\n"); - if (!prompt) exit (1); + if (exit_on_error) exit (1); goto next_command; } *(pend-1) = '\0'; @@ -472,7 +484,7 @@ script (int prompt) if (i == sizeof argv / sizeof argv[0]) { fprintf (stderr, "guestfish: too many arguments\n"); - if (!prompt) exit (1); + if (exit_on_error) exit (1); goto next_command; } @@ -480,7 +492,7 @@ script (int prompt) got_command: if (issue_command (cmd, argv) == -1) { - if (!prompt) exit (1); + if (exit_on_error) exit (1); } next_command:; diff --git a/fish/fish.h b/fish/fish.h index 40f1990..c9dd350 100644 --- a/fish/fish.h +++ b/fish/fish.h @@ -23,7 +23,6 @@ /* in fish.c */ extern guestfs_h *g; -extern int g_launched; extern int quit; extern int verbose; extern void pod2text (const char *heading, const char *body); diff --git a/guestfish.pod b/guestfish.pod index b464c71..e7a4ffa 100644 --- a/guestfish.pod +++ b/guestfish.pod @@ -202,6 +202,17 @@ will create a directory C on the host, and then export the contents of C on the mounted filesystem to C. (See C). +=head1 EXIT ON ERROR BEHAVIOUR + +By default, guestfish will ignore any errors when in interactive mode +(ie. taking commands from a human over a tty), and will exit on the +first error in non-interactive mode (scripts, commands given on the +command line). + +If you prefix a command with a I<-> character, then that command will +not cause guestfish to exit, even if that (one) command returns an +error. + =head1 COMMANDS =head2 help @@ -301,6 +312,11 @@ set, it uses C. =back +=head1 EXIT CODE + +guestfish returns I<0> if the commands completed without error, or +I<1> if there was an error. + =head1 SEE ALSO L, -- 1.8.3.1