X-Git-Url: http://git.hungrycats.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=driver%2Fsubprocs.c;h=465b03fd8b9f39d72ffb2022fae8cf86387845c5;hb=3c58fb6311db49c46f1670922933b27c6ea0c065;hp=166ae5996f573b5e7a4a24d04497268362b83676;hpb=ce3185de9d9705e259f2b60dd4b5509007fa17d4;p=xscreensaver diff --git a/driver/subprocs.c b/driver/subprocs.c index 166ae599..465b03fd 100644 --- a/driver/subprocs.c +++ b/driver/subprocs.c @@ -1,6 +1,5 @@ /* subprocs.c --- choosing, spawning, and killing screenhacks. - * xscreensaver, Copyright (c) 1991, 1992, 1993, 1995, 1997, 1998 - * Jamie Zawinski + * xscreensaver, Copyright (c) 1991-2001 Jamie Zawinski * * Permission to use, copy, modify, distribute, and sell this software and its * documentation for any purpose is hereby granted without fee, provided that @@ -22,39 +21,41 @@ #include /* not used for much... */ #ifndef ESRCH -#include +# include #endif #include /* sys/resource.h needs this for timeval */ -#ifndef VMS - -# include /* for setpriority() and PRIO_PROCESS */ +#ifdef HAVE_SYS_WAIT_H # include /* for waitpid() and associated macros */ +#endif -#else /* VMS */ - -# if __DECC_VER >= 50200000 -# include -# endif +#if (defined(HAVE_SETPRIORITY) && defined(PRIO_PROCESS)) || \ + defined(HAVE_SETRLIMIT) +# include /* for setpriority() and PRIO_PROCESS */ + /* and also setrlimit() and RLIMIT_AS */ +#endif +#ifdef VMS # include # include /* for close */ # include /* for getpid */ -# define pid_t int -# define fork vfork - +# define pid_t int +# define fork vfork #endif /* VMS */ #include /* for the signal names */ #if !defined(SIGCHLD) && defined(SIGCLD) -#define SIGCHLD SIGCLD +# define SIGCHLD SIGCLD #endif +#if 0 /* putenv() is declared in stdlib.h on modern linux systems. */ #ifdef HAVE_PUTENV extern int putenv (/* const char * */); /* getenv() is in stdlib.h... */ #endif +#endif + extern int kill (pid_t, int); /* signal() is in sys/signal.h... */ /* This file doesn't need the Xt headers, so stub these types out... */ @@ -67,13 +68,10 @@ extern int kill (pid_t, int); /* signal() is in sys/signal.h... */ #include "xscreensaver.h" #include "yarandom.h" - +#include "visual.h" /* for id_to_visual() */ extern saver_info *global_si_kludge; /* I hate C so much... */ -static void hack_subproc_environment (saver_screen_info *ssi); - - static void nice_subproc (int nice_level) { @@ -109,6 +107,64 @@ nice_subproc (int nice_level) } +/* RLIMIT_AS (called RLIMIT_VMEM on some systems) controls the maximum size + of a process's address space, i.e., the maximal brk(2) and mmap(2) values. + Setting this lets you put a cap on how much memory a process can allocate. + */ +#if defined(RLIMIT_VMEM) && !defined(RLIMIT_AS) +# define RLIMIT_AS RLIMIT_VMEM +#endif + +static void +limit_subproc_memory (int address_space_limit, Bool verbose_p) +{ +#if defined(HAVE_SETRLIMIT) && defined(RLIMIT_AS) + struct rlimit r; + + if (address_space_limit < 10 * 1024) /* let's not be crazy */ + return; + + if (getrlimit (RLIMIT_AS, &r) != 0) + { + char buf [512]; + sprintf (buf, "%s: getrlimit(RLIMIT_AS) failed", blurb()); + perror (buf); + return; + } + + r.rlim_cur = address_space_limit; + + if (setrlimit (RLIMIT_AS, &r) != 0) + { + char buf [512]; + sprintf (buf, "%s: setrlimit(RLIMIT_AS, {%d, %d}) failed", + blurb(), r.rlim_cur, r.rlim_max); + perror (buf); + return; + } + + if (verbose_p) + { + int i = address_space_limit; + char buf[100]; + if (i >= (1<<30) && i == ((i >> 30) << 30)) + sprintf(buf, "%dG", i >> 30); + else if (i >= (1<<20) && i == ((i >> 20) << 20)) + sprintf(buf, "%dM", i >> 20); + else if (i >= (1<<10) && i == ((i >> 10) << 10)) + sprintf(buf, "%dK", i >> 10); + else + sprintf(buf, "%d bytes", i); + + fprintf (stderr, "%s: limited pid %lu address space to %s.\n", + blurb(), (unsigned long) getpid (), buf); + } + +#endif /* HAVE_SETRLIMIT && RLIMIT_AS */ +} + + + #ifndef VMS static void @@ -172,9 +228,49 @@ exec_complex_command (const char *shell, const char *command) { char *av[5]; int ac = 0; - char *command2 = (char *) malloc (strlen (command) + 6); - memcpy (command2, "exec ", 5); - memcpy (command2 + 5, command, strlen (command) + 1); + char *command2 = (char *) malloc (strlen (command) + 10); + const char *s; + int got_eq = 0; + const char *after_vars; + + /* Skip leading whitespace. + */ + while (*command == ' ' || *command == '\t') + command++; + + /* If the string has a series of tokens with "=" in them at them, set + `after_vars' to point into the string after those tokens and any + trailing whitespace. Otherwise, after_vars == command. + */ + after_vars = command; + for (s = command; *s; s++) + { + if (*s == '=') got_eq = 1; + else if (*s == ' ') + { + if (got_eq) + { + while (*s == ' ' || *s == '\t') + s++; + after_vars = s; + got_eq = 0; + } + else + break; + } + } + + *command2 = 0; + strncat (command2, command, after_vars - command); + strcat (command2, "exec "); + strcat (command2, after_vars); + + /* We have now done these transformations: + "foo -x -y" ==> "exec foo -x -y" + "BLAT=foop foo -x" ==> "BLAT=foop exec foo -x" + "BLAT=foop A=b foo -x" ==> "BLAT=foop A=b exec foo -x" + */ + /* Invoke the shell as "/bin/sh -c 'exec prog -arg -arg ...'" */ av [ac++] = (char *) shell; @@ -248,7 +344,19 @@ exec_screenhack (saver_info *si, const char *command) saver_preferences *p = &si->prefs; #ifndef VMS - Bool hairy_p = !!strpbrk (command, "*?$&!<>[];`'\\\""); + Bool hairy_p = !!strpbrk (command, "*?$&!<>[];`'\\\"="); + /* note: = is in the above because of the sh syntax "FOO=bar cmd". */ + + if (getuid() == (uid_t) 0 || geteuid() == (uid_t) 0) + { + /* If you're thinking of commenting this out, think again. + If you do so, you will open a security hole. Mail jwz + so that he may enlighten you as to the error of your ways. + */ + fprintf (stderr, "%s: we're still running as root! Disaster!\n", + blurb()); + saver_exit (si, 1, 0); + } if (p->verbose_p) fprintf (stderr, "%s: spawning \"%s\" in pid %lu%s.\n", @@ -325,20 +433,27 @@ make_job (pid_t pid, const char *cmd) static char name [1024]; const char *in = cmd; char *out = name; + int got_eq = 0; + int first = 1; clean_job_list(); + AGAIN: while (isspace(*in)) in++; /* skip whitespace */ - while (!isspace(*in) && *in != ':') + while (!isspace(*in) && *in != ':') { + if (*in == '=') got_eq = 1; *out++ = *in++; /* snarf first token */ - while (isspace(*in)) in++; /* skip whitespace */ - if (*in == ':') /* token was a visual name; skip it. */ - { - in++; + } + + if (got_eq) /* if the first token was FOO=bar */ + { /* then get the next token instead. */ + got_eq = 0; out = name; - while (isspace(*in)) in++; /* skip whitespace */ - while (!isspace(*in)) *out++ = *in++; /* snarf first token */ + first = 0; + goto AGAIN; } + + while (isspace(*in)) in++; /* skip whitespace */ *out = 0; job->name = strdup(name); @@ -419,7 +534,7 @@ static void describe_dead_child (saver_info *, pid_t, int wait_status); static int block_sigchld_handler = 0; -static void +void block_sigchld (void) { #ifdef HAVE_SIGACTION @@ -432,7 +547,7 @@ block_sigchld (void) block_sigchld_handler++; } -static void +void unblock_sigchld (void) { #ifdef HAVE_SIGACTION @@ -703,35 +818,25 @@ init_sigchld (void) static Bool -select_visual_of_hack (saver_screen_info *ssi, const char *hack) +select_visual_of_hack (saver_screen_info *ssi, screenhack *hack) { saver_info *si = ssi->global; saver_preferences *p = &si->prefs; Bool selected; - static char vis [1024]; - const char *in = hack; - char *out = vis; - while (isspace(*in)) in++; /* skip whitespace */ - while (!isspace(*in) && *in != ':') - *out++ = *in++; /* snarf first token */ - while (isspace(*in)) in++; /* skip whitespace */ - *out = 0; - if (*in == ':') - selected = select_visual(ssi, vis); + if (hack->visual && *hack->visual) + selected = select_visual(ssi, hack->visual); else selected = select_visual(ssi, 0); - if (!selected && (p->verbose_p || si->demo_mode_p)) - { - if (*in == ':') in++; - while (isspace(*in)) in++; - fprintf (stderr, - (si->demo_mode_p - ? "%s: warning, no \"%s\" visual for \"%s\".\n" - : "%s: no \"%s\" visual; skipping \"%s\".\n"), - blurb(), (vis ? vis : "???"), in); - } + if (!selected && (p->verbose_p || si->demoing_p)) + fprintf (stderr, + (si->demoing_p + ? "%s: warning, no \"%s\" visual for \"%s\".\n" + : "%s: no \"%s\" visual; skipping \"%s\".\n"), + blurb(), + (hack->visual && *hack->visual ? hack->visual : "???"), + hack->command); return selected; } @@ -745,76 +850,81 @@ spawn_screenhack_1 (saver_screen_info *ssi, Bool first_time_p) raise_window (si, first_time_p, True, False); XFlush (si->dpy); - if (p->screenhacks_count || si->demo_mode_p) + if (p->screenhacks_count) { - char *hack; + screenhack *hack; pid_t forked; char buf [255]; int new_hack; + int retry_count = 0; + Bool force = False; - if (si->demo_mode_p) - { - hack = si->demo_hack; + AGAIN: + + if (p->screenhacks_count == 1) + /* If there is only one hack in the list, there is no choice. */ + new_hack = 0; + + else if (si->selection_mode == -1) + /* Select the next hack, wrapping. */ + new_hack = (ssi->current_hack + 1) % p->screenhacks_count; - /* Ignore visual-selection failure if in demo mode. */ - (void) select_visual_of_hack (ssi, hack); + else if (si->selection_mode == -2) + /* Select the previous hack, wrapping. */ + new_hack = ((ssi->current_hack + p->screenhacks_count - 1) + % p->screenhacks_count); + + else if (si->selection_mode > 0) + /* Select a specific hack, by number. No negotiation. */ + { + new_hack = ((si->selection_mode - 1) % p->screenhacks_count); + force = True; } else { - int retry_count = 0; - - AGAIN: - if (p->screenhacks_count == 1) - new_hack = 0; - else if (si->next_mode_p == 1) - new_hack = (ssi->current_hack + 1) % p->screenhacks_count; - else if (si->next_mode_p == 2) - new_hack = ((ssi->current_hack + p->screenhacks_count - 1) - % p->screenhacks_count); - else - while ((new_hack = random () % p->screenhacks_count) - == ssi->current_hack) - ; - ssi->current_hack = new_hack; - hack = p->screenhacks[ssi->current_hack]; + /* Select a random hack (but not the one we just ran.) */ + while ((new_hack = random () % p->screenhacks_count) + == ssi->current_hack) + ; + } - if (!select_visual_of_hack (ssi, hack)) + ssi->current_hack = new_hack; + hack = p->screenhacks[ssi->current_hack]; + + /* If the hack is disabled, or there is no visual for this hack, + then try again (move forward, or backward, or re-randomize.) + Unless this hack was specified explicitly, in which case, + use it regardless. + */ + if (force) + select_visual_of_hack (ssi, hack); + + if (!force && + (!hack->enabled_p || + !select_visual_of_hack (ssi, hack))) + { + if (++retry_count > (p->screenhacks_count*4)) { - if (++retry_count > (p->screenhacks_count*4)) - { - /* Uh, oops. Odds are, there are no suitable visuals, - and we're looping. Give up. (This is totally lame, - what we should do is make a list of suitable hacks at - the beginning, then only loop over them.) - */ - if (p->verbose_p) - fprintf(stderr, - "%s: no suitable visuals for these programs.\n", - blurb()); - return; - } - else - goto AGAIN; + /* Uh, oops. Odds are, there are no suitable visuals, + and we're looping. Give up. (This is totally lame, + what we should do is make a list of suitable hacks at + the beginning, then only loop over them.) + */ + if (p->verbose_p) + fprintf(stderr, + "%s: no suitable visuals for these programs.\n", + blurb()); + return; } + else + goto AGAIN; } - si->next_mode_p = 0; - - /* If there's a visual description on the front of the command, nuke it. + /* Turn off "next" and "prev" modes now, but "demo" mode is only + turned off by explicit action. */ - { - char *in = hack; - while (isspace(*in)) in++; /* skip whitespace */ - hack = in; - while (!isspace(*in) && *in != ':') in++; /* snarf first token */ - while (isspace(*in)) in++; /* skip whitespace */ - if (*in == ':') - { - in++; - while (isspace(*in)) in++; - hack = in; - } - } + if (si->selection_mode < 0) + si->selection_mode = 0; switch ((int) (forked = fork ())) { @@ -827,14 +937,15 @@ spawn_screenhack_1 (saver_screen_info *ssi, Bool first_time_p) case 0: close (ConnectionNumber (si->dpy)); /* close display fd */ nice_subproc (p->nice_inferior); /* change process priority */ + limit_subproc_memory (p->inferior_memory_limit, p->verbose_p); hack_subproc_environment (ssi); /* set $DISPLAY */ - exec_screenhack (si, hack); /* this does not return */ + exec_screenhack (si, hack->command); /* this does not return */ abort(); break; default: ssi->pid = forked; - (void) make_job (forked, hack); + (void) make_job (forked, hack->command); break; } } @@ -844,22 +955,21 @@ spawn_screenhack_1 (saver_screen_info *ssi, Bool first_time_p) void spawn_screenhack (saver_info *si, Bool first_time_p) { - int i; - - if (!monitor_powered_on_p (si)) + if (monitor_powered_on_p (si)) { - if (si->prefs.verbose_p) - fprintf (stderr, - "%s: server reports that monitor has powered down; " - "not launching a new hack.\n", blurb()); - return; + int i; + for (i = 0; i < si->nscreens; i++) + { + saver_screen_info *ssi = &si->screens[i]; + spawn_screenhack_1 (ssi, first_time_p); + } } + else if (si->prefs.verbose_p) + fprintf (stderr, + "%s: X says monitor has powered down; " + "not launching a hack.\n", blurb()); - for (i = 0; i < si->nscreens; i++) - { - saver_screen_info *ssi = &si->screens[i]; - spawn_screenhack_1 (ssi, first_time_p); - } + store_saver_status (si); /* store current hack numbers */ } @@ -915,65 +1025,45 @@ emergency_kill_subproc (saver_info *si) Bool screenhack_running_p (saver_info *si) { - Bool result = True; + Bool any_running_p = False; int i; for (i = 0; i < si->nscreens; i++) { saver_screen_info *ssi = &si->screens[i]; - if (!ssi->pid) - result = False; + if (ssi->pid) any_running_p = True; } - return result; + return any_running_p; } -/* Restarting the xscreensaver process from scratch. */ +/* Environment variables. */ -static char **saved_argv; +/* Modifies $PATH in the current environment, so that if DEFAULT_PATH_PREFIX + is defined, the xscreensaver daemon will search that directory for hacks. + */ void -save_argv (int argc, char **argv) +hack_environment (saver_info *si) { - saved_argv = (char **) malloc ((argc + 2) * sizeof (char *)); - saved_argv [argc] = 0; - while (argc--) +#if defined(HAVE_PUTENV) && defined(DEFAULT_PATH_PREFIX) + static const char *def_path = DEFAULT_PATH_PREFIX; + if (def_path && *def_path) { - int i = strlen (argv [argc]) + 1; - saved_argv [argc] = (char *) malloc (i); - memcpy (saved_argv [argc], argv [argc], i); + const char *opath = getenv("PATH"); + char *npath = (char *) malloc(strlen(def_path) + strlen(opath) + 20); + strcpy (npath, "PATH="); + strcat (npath, def_path); + strcat (npath, ":"); + strcat (npath, opath); + + if (putenv (npath)) + abort (); } +#endif /* HAVE_PUTENV && DEFAULT_PATH_PREFIX */ } -void -restart_process (saver_info *si) -{ - fflush (real_stdout); - fflush (real_stderr); - execvp (saved_argv [0], saved_argv); /* shouldn't return */ - { - char buf [512]; - sprintf (buf, "%s: could not restart process", blurb()); - perror(buf); - fflush(stderr); - } -} -/* Like restart_process(), but ensures that when it restarts, - it comes up in demo-mode. */ void -demo_mode_restart_process (saver_info *si) -{ - int i; - for (i = 0; saved_argv [i]; i++); - /* add the -initial-demo-mode switch; save_argv() left room for this. */ - saved_argv [i] = "-initial-demo-mode"; - saved_argv [i+1] = 0; - restart_process (si); /* shouldn't return */ - saved_argv [i] = 0; - XBell(si->dpy, 0); -} - -static void hack_subproc_environment (saver_screen_info *ssi) { /* Store $DISPLAY into the environment, so that the $DISPLAY variable that @@ -994,7 +1084,6 @@ hack_subproc_environment (saver_screen_info *ssi) for (screen_number = 0; screen_number < si->nscreens; screen_number++) if (ssi == &si->screens[screen_number]) break; - if (screen_number >= si->nscreens) abort(); strcpy (ndpy, "DISPLAY="); s = ndpy + strlen(ndpy); @@ -1015,23 +1104,155 @@ hack_subproc_environment (saver_screen_info *ssi) #endif /* HAVE_PUTENV */ } + +/* GL crap */ + +Visual * +get_best_gl_visual (saver_screen_info *ssi) +{ + saver_info *si = ssi->global; + pid_t forked; + int fds [2]; + int in, out; + char buf[1024]; + + char *av[10]; + int ac = 0; + + av[ac++] = "xscreensaver-gl-helper"; + av[ac] = 0; + + if (pipe (fds)) + { + perror ("error creating pipe:"); + return 0; + } + + in = fds [0]; + out = fds [1]; + + switch ((int) (forked = fork ())) + { + case -1: + { + sprintf (buf, "%s: couldn't fork", blurb()); + perror (buf); + saver_exit (si, 1, 0); + } + case 0: + { + int stdout_fd = 1; + + close (in); /* don't need this one */ + close (ConnectionNumber (si->dpy)); /* close display fd */ + + if (dup2 (out, stdout_fd) < 0) /* pipe stdout */ + { + perror ("could not dup() a new stdout:"); + return 0; + } + hack_subproc_environment (ssi); /* set $DISPLAY */ + + execvp (av[0], av); /* shouldn't return. */ + + if (errno != ENOENT || si->prefs.verbose_p) + { + /* Ignore "no such file or directory" errors, unless verbose. + Issue all other exec errors, though. */ + sprintf (buf, "%s: running %s", blurb(), av[0]); + perror (buf); + } + exit (1); /* exits fork */ + break; + } + default: + { + int result = 0; + int wait_status = 0; + + FILE *f = fdopen (in, "r"); + unsigned long v = 0; + char c; + + close (out); /* don't need this one */ + + *buf = 0; + fgets (buf, sizeof(buf)-1, f); + fclose (f); + + /* Wait for the child to die. */ + waitpid (-1, &wait_status, 0); + + if (1 == sscanf (buf, "0x%x %c", &v, &c)) + result = (int) v; + + if (result == 0) + { + if (si->prefs.verbose_p) + fprintf (stderr, "%s: %s did not report a GL visual!\n", + blurb(), av[0]); + return 0; + } + else + { + Visual *v = id_to_visual (ssi->screen, result); + if (si->prefs.verbose_p) + fprintf (stderr, "%s: %s says the GL visual is 0x%X%s.\n", + blurb(), av[0], result, + (v == ssi->default_visual ? " (the default)" : "")); + return v; + } + } + } + + abort(); +} + + + +/* Restarting the xscreensaver process from scratch. */ + +static char **saved_argv; void -hack_environment (saver_info *si) +save_argv (int argc, char **argv) { -#if defined(HAVE_PUTENV) && defined(DEFAULT_PATH_PREFIX) - static const char *def_path = DEFAULT_PATH_PREFIX; - if (def_path && *def_path) + saved_argv = (char **) calloc (argc+2, sizeof (char *)); + saved_argv [argc] = 0; + while (argc--) { - const char *opath = getenv("PATH"); - char *npath = (char *) malloc(strlen(def_path) + strlen(opath) + 20); - strcpy (npath, "PATH="); - strcat (npath, def_path); - strcat (npath, ":"); - strcat (npath, opath); + int i = strlen (argv [argc]) + 1; + saved_argv [argc] = (char *) malloc (i); + memcpy (saved_argv [argc], argv [argc], i); + } +} - if (putenv (npath)) - abort (); + +/* Re-execs the process with the arguments in saved_argv. + Does not return unless there was an error. + */ +void +restart_process (saver_info *si) +{ + if (si->prefs.verbose_p) + { + int i; + fprintf (real_stderr, "%s: re-executing", blurb()); + for (i = 0; saved_argv[i]; i++) + fprintf (real_stderr, " %s", saved_argv[i]); + fprintf (real_stderr, "\n"); } -#endif /* HAVE_PUTENV && DEFAULT_PATH_PREFIX */ + describe_uids (si, real_stderr); + fprintf (real_stderr, "\n"); + + fflush (real_stdout); + fflush (real_stderr); + execvp (saved_argv [0], saved_argv); /* shouldn't return */ + { + char buf [512]; + sprintf (buf, "%s: could not restart process", blurb()); + perror(buf); + fflush(stderr); + } + XBell(si->dpy, 0); }