X-Git-Url: http://git.hungrycats.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=driver%2Fsubprocs.c;h=e97fc928944ba66a5f30de387d89c2661ef24aae;hb=8eb2873d7054e705c4e83f22d18c40946a9e2529;hp=50dd82b8a521459493a18f7506347a8be6aa9927;hpb=f3e0240915ed9f9b3a61781f5c7002d587563fe0;p=xscreensaver diff --git a/driver/subprocs.c b/driver/subprocs.c index 50dd82b8..e97fc928 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 - * 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 @@ -22,44 +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 */ -#ifndef NO_SETUID -#include /* for getpwnam() and struct passwd */ -#include /* for getgrgid() and struct group */ -#endif /* NO_SETUID */ - #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... */ @@ -72,13 +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_environment (saver_screen_info *ssi); - - static void nice_subproc (int nice_level) { @@ -93,7 +86,7 @@ nice_subproc (int nice_level) if (nice (n) == -1 && errno != 0) { char buf [512]; - sprintf (buf, "%s: nice(%d) failed", progname, n); + sprintf (buf, "%s: nice(%d) failed", blurb(), n); perror (buf); } } @@ -102,18 +95,76 @@ nice_subproc (int nice_level) { char buf [512]; sprintf (buf, "%s: setpriority(PRIO_PROCESS, %lu, %d) failed", - progname, (unsigned long) getpid(), nice_level); + blurb(), (unsigned long) getpid(), nice_level); perror (buf); } #else fprintf (stderr, "%s: don't know how to change process priority on this system.\n", - progname); + blurb()); #endif } +/* 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, {%lu, %lu}) 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 @@ -133,7 +184,7 @@ exec_simple_command (const char *command) { char buf [512]; - sprintf (buf, "%s: could not execute \"%s\"", progname, av[0]); + sprintf (buf, "%s: could not execute \"%s\"", blurb(), av[0]); perror (buf); if (errno == ENOENT && @@ -177,9 +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; @@ -191,7 +282,7 @@ exec_complex_command (const char *shell, const char *command) { char buf [512]; - sprintf (buf, "%s: execvp(\"%s\") failed", progname, av[0]); + sprintf (buf, "%s: execvp(\"%s\") failed", blurb(), av[0]); perror (buf); fflush(stderr); fflush(stdout); @@ -214,7 +305,7 @@ exec_vms_command (const char *command) static void -exec_screenhack (saver_info *si, const char *command) +exec_screenhack (saver_screen_info *ssi, const char *command) { /* I don't believe what a sorry excuse for an operating system UNIX is! @@ -250,15 +341,29 @@ exec_screenhack (saver_info *si, const char *command) what I've seen in Emacs, dealing with process groups isn't especially portable.) */ + saver_info *si = ssi->global; 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) - printf ("%s: spawning \"%s\" in pid %lu%s.\n", - progname, command, (unsigned long) getpid (), - (hairy_p ? " (via shell)" : "")); + fprintf (stderr, "%s: %d: spawning \"%s\" in pid %lu%s.\n", + blurb(), ssi->number, command, + (unsigned long) getpid (), + (hairy_p ? " (via shell)" : "")); if (hairy_p) /* If it contains any shell metacharacters, do it the hard way, @@ -270,7 +375,8 @@ exec_screenhack (saver_info *si, const char *command) #else /* VMS */ if (p->verbose_p) - printf ("%s: spawning \"%s\" in pid %lu.\n", progname, command, getpid()); + fprintf (stderr, "%s: %d: spawning \"%s\" in pid %lu.\n", + blurb(), ssi->number, command, getpid()); exec_vms_command (command); #endif /* VMS */ @@ -295,21 +401,23 @@ enum job_status { struct screenhack_job { char *name; pid_t pid; + int screen; enum job_status status; struct screenhack_job *next; }; static struct screenhack_job *jobs = 0; -#ifdef DEBUG -static void +/* for debugging -- nothing calls this, but it's useful to invoke from gdb. */ +void show_job_list (void) { struct screenhack_job *job; - fprintf(stderr, "%s: job list:\n", progname); + fprintf(stderr, "%s: job list:\n", blurb()); for (job = jobs; job; job = job->next) - fprintf (stderr, " %5ld: (%s) %s\n", + fprintf (stderr, " %5ld: %2d: (%s) %s\n", (long) job->pid, + job->screen, (job->status == job_running ? "running" : job->status == job_stopped ? "stopped" : job->status == job_killed ? " killed" : @@ -317,37 +425,44 @@ show_job_list (void) job->name); fprintf (stderr, "\n"); } -#endif static void clean_job_list (void); static struct screenhack_job * -make_job (pid_t pid, const char *cmd) +make_job (pid_t pid, int screen, const char *cmd) { struct screenhack_job *job = (struct screenhack_job *) malloc (sizeof(*job)); 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); job->pid = pid; + job->screen = screen; job->status = job_running; job->next = jobs; jobs = job; @@ -418,9 +533,38 @@ static void describe_dead_child (saver_info *, pid_t, int wait_status); #endif -/* Semaphore to temporarily turn the SIGCHLD handler into a no-op. */ +/* Semaphore to temporarily turn the SIGCHLD handler into a no-op. + Don't alter this directly -- use block_sigchld() / unblock_sigchld(). + */ static int block_sigchld_handler = 0; + +void +block_sigchld (void) +{ +#ifdef HAVE_SIGACTION + sigset_t child_set; + sigemptyset (&child_set); + sigaddset (&child_set, SIGCHLD); + sigprocmask (SIG_BLOCK, &child_set, 0); +#endif /* HAVE_SIGACTION */ + + block_sigchld_handler++; +} + +void +unblock_sigchld (void) +{ +#ifdef HAVE_SIGACTION + sigset_t child_set; + sigemptyset(&child_set); + sigaddset(&child_set, SIGCHLD); + sigprocmask(SIG_UNBLOCK, &child_set, 0); +#endif /* HAVE_SIGACTION */ + + block_sigchld_handler--; +} + static int kill_job (saver_info *si, pid_t pid, int signal) { @@ -434,7 +578,7 @@ kill_job (saver_info *si, pid_t pid, int signal) /* This function should not be called from the signal handler. */ abort(); - block_sigchld_handler++; /* we control the horizontal... */ + block_sigchld(); /* we control the horizontal... */ job = find_job (pid); if (!job || @@ -443,7 +587,7 @@ kill_job (saver_info *si, pid_t pid, int signal) { if (p->verbose_p) fprintf (stderr, "%s: no child %ld to signal!\n", - progname, (long) pid); + blurb(), (long) pid); goto DONE; } @@ -457,31 +601,27 @@ kill_job (saver_info *si, pid_t pid, int signal) default: abort(); } -#ifdef SIGSTOP if (p->verbose_p) - fprintf (stderr, "%s: %s pid %lu.\n", progname, - (signal == SIGTERM ? "killing" : - signal == SIGSTOP ? "suspending" : - signal == SIGCONT ? "resuming" : "signalling"), - (unsigned long) job->pid); -#else /* !SIGSTOP */ - if (p->verbose_p) - fprintf (stderr, "%s: %s pid %lu.\n", progname, "killing", - (unsigned long) job->pid); -#endif /* !SIGSTOP */ + fprintf (stderr, "%s: %d: %s pid %lu (%s)\n", + blurb(), job->screen, + (job->status == job_killed ? "killing" : + job->status == job_stopped ? "suspending" : "resuming"), + (unsigned long) job->pid, + job->name); status = kill (job->pid, signal); if (p->verbose_p && status < 0) { if (errno == ESRCH) - fprintf (stderr, "%s: child process %lu (%s) was already dead.\n", - progname, job->pid, job->name); + fprintf (stderr, + "%s: %d: child process %lu (%s) was already dead.\n", + blurb(), job->screen, job->pid, job->name); else { char buf [1024]; - sprintf (buf, "%s: couldn't kill child process %lu (%s)", - progname, job->pid, job->name); + sprintf (buf, "%s: %d: couldn't kill child process %lu (%s)", + blurb(), job->screen, job->pid, job->name); perror (buf); } } @@ -489,7 +629,7 @@ kill_job (saver_info *si, pid_t pid, int signal) await_dying_children (si); DONE: - block_sigchld_handler--; + unblock_sigchld(); if (block_sigchld_handler < 0) abort(); @@ -504,24 +644,22 @@ sigchld_handler (int sig) { saver_info *si = global_si_kludge; /* I hate C so much... */ -#ifdef DEBUG if (si->prefs.debug_p) - fprintf(stderr, "%s: got SIGCHLD%s\n", progname, + fprintf(stderr, "%s: got SIGCHLD%s\n", blurb(), (block_sigchld_handler ? " (blocked)" : "")); -#endif if (block_sigchld_handler < 0) abort(); else if (block_sigchld_handler == 0) { - block_sigchld_handler++; + block_sigchld(); await_dying_children (si); - block_sigchld_handler--; + unblock_sigchld(); } init_sigchld(); } -#endif +#endif /* SIGCHLD */ #ifndef VMS @@ -535,14 +673,16 @@ await_dying_children (saver_info *si) errno = 0; kid = waitpid (-1, &wait_status, WNOHANG|WUNTRACED); -#ifdef DEBUG + if (si->prefs.debug_p) - if (kid < 0 && errno) - fprintf (stderr, "%s: waitpid(-1) ==> %ld (%d)\n", progname, - (long) kid, errno); - else - fprintf (stderr, "%s: waitpid(-1) ==> %ld\n", progname, (long) kid); -#endif + { + if (kid < 0 && errno) + fprintf (stderr, "%s: waitpid(-1) ==> %ld (%d)\n", blurb(), + (long) kid, errno); + else + fprintf (stderr, "%s: waitpid(-1) ==> %ld\n", blurb(), + (long) kid); + } /* 0 means no more children to reap. -1 means error -- except "interrupted system call" isn't a "real" @@ -563,6 +703,7 @@ describe_dead_child (saver_info *si, pid_t kid, int wait_status) saver_preferences *p = &si->prefs; struct screenhack_job *job = find_job (kid); const char *name = job ? job->name : ""; + int screen_no = job ? job->screen : 0; if (WIFEXITED (wait_status)) { @@ -581,11 +722,11 @@ describe_dead_child (saver_info *si, pid_t kid, int wait_status) (exit_status != 0 && (p->verbose_p || job->status != job_killed))) fprintf (stderr, - "%s: child pid %lu (%s) exited abnormally (code %d).\n", - progname, (unsigned long) kid, name, exit_status); + "%s: %d: child pid %lu (%s) exited abnormally (code %d).\n", + blurb(), screen_no, (unsigned long) kid, name, exit_status); else if (p->verbose_p) - printf ("%s: child pid %lu (%s) exited normally.\n", - progname, (unsigned long) kid, name); + fprintf (stderr, "%s: %d: child pid %lu (%s) exited normally.\n", + blurb(), screen_no, (unsigned long) kid, name); if (job) job->status = job_dead; @@ -596,8 +737,8 @@ describe_dead_child (saver_info *si, pid_t kid, int wait_status) !job || job->status != job_killed || WTERMSIG (wait_status) != SIGTERM) - fprintf (stderr, "%s: child pid %lu (%s) terminated with %s.\n", - progname, (unsigned long) kid, name, + fprintf (stderr, "%s: %d: child pid %lu (%s) terminated with %s.\n", + blurb(), screen_no, (unsigned long) kid, name, signal_name (WTERMSIG(wait_status))); if (job) @@ -607,7 +748,7 @@ describe_dead_child (saver_info *si, pid_t kid, int wait_status) { if (p->verbose_p) fprintf (stderr, "%s: child pid %lu (%s) stopped with %s.\n", - progname, (unsigned long) kid, name, + blurb(), (unsigned long) kid, name, signal_name (WSTOPSIG (wait_status))); if (job) @@ -616,7 +757,7 @@ describe_dead_child (saver_info *si, pid_t kid, int wait_status) else { fprintf (stderr, "%s: child pid %lu (%s) died in a mysterious way!", - progname, (unsigned long) kid, name); + blurb(), (unsigned long) kid, name); if (job) job->status = job_dead; } @@ -641,13 +782,37 @@ void init_sigchld (void) { #ifdef SIGCHLD + +# ifdef HAVE_SIGACTION /* Thanks to Tom Kelly */ + + static Bool sigchld_initialized_p = 0; + if (!sigchld_initialized_p) + { + struct sigaction action, old; + + action.sa_handler = sigchld_handler; + sigemptyset(&action.sa_mask); + action.sa_flags = 0; + + if (sigaction(SIGCHLD, &action, &old) < 0) + { + char buf [255]; + sprintf (buf, "%s: couldn't catch SIGCHLD", blurb()); + perror (buf); + } + sigchld_initialized_p = True; + } + +# else /* !HAVE_SIGACTION */ + if (((long) signal (SIGCHLD, sigchld_handler)) == -1L) { char buf [255]; - sprintf (buf, "%s: couldn't catch SIGCHLD", progname); + sprintf (buf, "%s: couldn't catch SIGCHLD", blurb()); perror (buf); } -#endif +# endif /* !HAVE_SIGACTION */ +#endif /* SIGCHLD */ } @@ -655,35 +820,25 @@ 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"), - progname, (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; } @@ -697,96 +852,127 @@ 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; - - if (si->demo_mode_p) + int retry_count = 0; + Bool force = False; + + AGAIN: + + if (p->screenhacks_count < 1) + { + /* No hacks at all */ + new_hack = -1; + } + else if (si->selection_mode == -1) + { + /* Select the next hack, wrapping. */ + new_hack = (ssi->current_hack + 1) % p->screenhacks_count; + } + else if (si->selection_mode == -2) + { + /* Select the previous hack, wrapping. */ + if (ssi->current_hack < 0) + new_hack = p->screenhacks_count - 1; + else + new_hack = ((ssi->current_hack + p->screenhacks_count - 1) + % p->screenhacks_count); + } + else if (si->selection_mode > 0) { - hack = si->demo_hack; - - /* Ignore visual-selection failure if in demo mode. */ - (void) select_visual_of_hack (ssi, hack); + /* Select a specific hack, by number (via the ACTIVATE command.) */ + new_hack = ((si->selection_mode - 1) % p->screenhacks_count); + force = True; } - else + else if (p->mode == ONE_HACK && + p->selected_hack >= 0) { - 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 specific hack, by number (via "One Saver" mode.) */ + new_hack = p->selected_hack; + force = True; + } + else if (p->mode == BLANK_ONLY || p->mode == DONT_BLANK) + { + new_hack = -1; + } + else /* (p->mode == RANDOM_HACKS) */ + { + /* 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)) + if (new_hack < 0) /* don't run a hack */ + { + ssi->current_hack = -1; + if (si->selection_mode < 0) + si->selection_mode = 0; + return; + } + + 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", - progname); - 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 ())) { case -1: - sprintf (buf, "%s: couldn't fork", progname); + sprintf (buf, "%s: couldn't fork", blurb()); perror (buf); restore_real_vroot (si); - saver_exit (si, 1); + saver_exit (si, 1, 0); case 0: close (ConnectionNumber (si->dpy)); /* close display fd */ nice_subproc (p->nice_inferior); /* change process priority */ - hack_environment (ssi); /* set $DISPLAY */ - exec_screenhack (si, hack); /* this does not return */ + limit_subproc_memory (p->inferior_memory_limit, p->verbose_p); + hack_subproc_environment (ssi); /* set $DISPLAY */ + exec_screenhack (ssi, hack->command); /* this does not return */ abort(); break; default: ssi->pid = forked; - (void) make_job (forked, hack); + (void) make_job (forked, ssi->number, hack->command); break; } } @@ -796,12 +982,21 @@ spawn_screenhack_1 (saver_screen_info *ssi, Bool first_time_p) void spawn_screenhack (saver_info *si, Bool first_time_p) { - int i; - for (i = 0; i < si->nscreens; i++) + if (monitor_powered_on_p (si)) { - saver_screen_info *ssi = &si->screens[i]; - spawn_screenhack_1 (ssi, first_time_p); + 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()); + + store_saver_status (si); /* store current hack numbers */ } @@ -841,7 +1036,7 @@ emergency_kill_subproc (saver_info *si) int i; #ifdef SIGCHLD signal (SIGCHLD, SIG_IGN); -#endif +#endif /* SIGCHLD */ for (i = 0; i < si->nscreens; i++) { @@ -857,66 +1052,46 @@ 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", progname); - 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 -demo switch; save_argv() left room for this. */ - saved_argv [i] = "-demo"; - saved_argv [i+1] = 0; - restart_process (si); /* shouldn't return */ - saved_argv [i] = 0; - XBell(si->dpy, 0); -} - -static void -hack_environment (saver_screen_info *ssi) +hack_subproc_environment (saver_screen_info *ssi) { /* Store $DISPLAY into the environment, so that the $DISPLAY variable that the spawned processes inherit is correct. First, it must be on the same @@ -930,14 +1105,8 @@ hack_environment (saver_screen_info *ssi) saver_info *si = ssi->global; const char *odpy = DisplayString (si->dpy); char *ndpy = (char *) malloc(strlen(odpy) + 20); - int screen_number; char *s; - 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); strcpy (s, odpy); @@ -947,7 +1116,7 @@ hack_environment (saver_screen_info *ssi) while (isdigit(*s)) s++; /* skip over dpy number */ while (*s == '.') s++; /* skip over dot */ if (s[-1] != '.') *s++ = '.'; /* put on a dot */ - sprintf(s, "%d", screen_number); /* put on screen number */ + sprintf(s, "%d", ssi->number); /* put on screen number */ /* Allegedly, BSD 4.3 didn't have putenv(), but nobody runs such systems any more, right? It's not Posix, but everyone seems to have it. */ @@ -958,127 +1127,155 @@ hack_environment (saver_screen_info *ssi) } -/* Change the uid/gid of the screensaver process, so that it is safe for it - to run setuid root (which it needs to do on some systems to read the - encrypted passwords from the passwd file.) - - hack_uid() is run before opening the X connection, so that XAuth works. - hack_uid_warn() is called after the connection is opened and the command - line arguments are parsed, so that the messages from hack_uid() get - printed after we know whether we're in `verbose' mode. - */ +/* GL crap */ -#ifndef NO_SETUID +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]; -static int hack_uid_errno; -static char hack_uid_buf [255], *hack_uid_error; + char *av[10]; + int ac = 0; -void -hack_uid (saver_info *si) -{ + av[ac++] = "xscreensaver-gl-helper"; + av[ac] = 0; - /* If we've been run as setuid or setgid to someone else (most likely root) - turn off the extra permissions so that random user-specified programs - don't get special privileges. (On some systems it might be necessary - to install this as setuid root in order to read the passwd file to - implement lock-mode...) - */ - setgid (getgid ()); - setuid (getuid ()); - - hack_uid_errno = 0; - hack_uid_error = 0; - - /* If we're being run as root (as from xdm) then switch the user id - to something safe. */ - if (getuid () == 0) + if (pipe (fds)) { - struct passwd *p; - /* Locking can't work when running as root, because we have no way of - knowing what the user id of the logged in user is (so we don't know - whose password to prompt for.) - */ - si->locking_disabled_p = True; - si->nolock_reason = "running as root"; - p = getpwnam ("nobody"); - if (! p) p = getpwnam ("daemon"); - if (! p) p = getpwnam ("bin"); - if (! p) p = getpwnam ("sys"); - if (! p) - { - hack_uid_error = "couldn't find safe uid; running as root."; - hack_uid_errno = -1; - } - else - { - struct group *g = getgrgid (p->pw_gid); - hack_uid_error = hack_uid_buf; - sprintf (hack_uid_error, "changing uid/gid to %s/%s (%ld/%ld).", - p->pw_name, (g ? g->gr_name : "???"), - (long) p->pw_uid, (long) p->pw_gid); - - /* Change the gid to be a safe one. If we can't do that, then - print a warning. We change the gid before the uid so that we - change the gid while still root. */ - if (setgid (p->pw_gid) != 0) - { - hack_uid_errno = errno; - sprintf (hack_uid_error, "couldn't set gid to %s (%ld)", - (g ? g->gr_name : "???"), (long) p->pw_gid); - } + perror ("error creating pipe:"); + return 0; + } - /* Now change the uid to be a safe one. */ - if (setuid (p->pw_uid) != 0) - { - hack_uid_errno = errno; - sprintf (hack_uid_error, "couldn't set uid to %s (%ld)", - p->pw_name, (long) p->pw_uid); - } - } + 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: %d: %s: GL visual is 0x%X%s.\n", + blurb(), ssi->number, + av[0], result, + (v == ssi->default_visual ? " (default)" : "")); + return v; + } + } } -#ifndef NO_LOCKING - else /* disable locking if already being run as "someone else" */ - { - struct passwd *p = getpwuid (getuid ()); - if (!p || - !strcmp (p->pw_name, "root") || - !strcmp (p->pw_name, "nobody") || - !strcmp (p->pw_name, "daemon") || - !strcmp (p->pw_name, "bin") || - !strcmp (p->pw_name, "sys")) - { - si->locking_disabled_p = True; - si->nolock_reason = hack_uid_buf; - sprintf (si->nolock_reason, "running as %s", p->pw_name); - } - } -#endif /* NO_LOCKING */ + + abort(); } + + +/* Restarting the xscreensaver process from scratch. */ + +static char **saved_argv; + void -hack_uid_warn (saver_info *si) +save_argv (int argc, char **argv) { - saver_preferences *p = &si->prefs; - - if (! hack_uid_error) - ; - else if (hack_uid_errno == 0) + saved_argv = (char **) calloc (argc+2, sizeof (char *)); + saved_argv [argc] = 0; + while (argc--) { - if (p->verbose_p) - printf ("%s: %s\n", progname, hack_uid_error); + int i = strlen (argv [argc]) + 1; + saved_argv [argc] = (char *) malloc (i); + memcpy (saved_argv [argc], argv [argc], i); } - else +} + + +/* 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) { - char buf [255]; - sprintf (buf, "%s: %s", progname, hack_uid_error); - if (hack_uid_errno == -1) - fprintf (stderr, "%s\n", buf); - else - { - errno = hack_uid_errno; - perror (buf); - } + 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"); } -} + describe_uids (si, real_stderr); + fprintf (real_stderr, "\n"); -#endif /* !NO_SETUID */ + 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); +}