* #!/usr/bin/cgi-fcgi-interp [<options>],<interpreter>
*/
/*
- * cgi-fcgi-interp.[ch] - C helpers common to the whole of chiark-utils
+ * cgi-fcgi-interp.[ch] - Convenience wrapper for cgi-fcgi
*
* Copyright 2016 Ian Jackson
* Copyright 1982,1986,1993 The Regents of the University of California
* The real interpreter to use. Eg "perl". Need not
* be an absolute path; will be fed to execvp.
*
+ * -G<ident-info>
+ * Add <ident-info> to the unique identifying information for
+ * this fcgi program. May be repeated; order is significant.
+ *
+ * -E<ident-info-env-var>
+ * Look <ident-info-env-var> up in the environment and add
+ * <ident-info-env-var>=<value> as if specified with -G. If
+ * the variable is unset in the environment, it is as if
+ * -G<ident-info-env-var> was specified.
+ *
* -g<ident>
* Use <ident> rather than hex(sha256(<interp>\0<script>\0))
* as the basename of the leafname of the fcgi rendezvous
#include <unistd.h>
#include <fcntl.h>
#include <pwd.h>
-#include <err.h>
#include <time.h>
#include <signal.h>
#include <sys/wait.h>
+#include <syslog.h>
#include <nettle/sha.h>
#include "myopt.h"
-#define die common_die
-#define diee common_diee
-
#define MINHEXHASH 33
#define STAGE2_VAR "CHIARKUTILS_CGIFCGIINTERP_STAGE2"
static struct sha256_ctx identsc;
-const char *stage2;
+static bool logging;
+static const char *stage2;
-void diee(const char *m) {
- err(127, "error: %s failed", m);
+static void vmsgcore(int estatus, int errnoval, const char *fmt, va_list al) {
+ int r;
+
+ if (logging) {
+ const char *fmt_use = fmt;
+ char *fmt_free = 0;
+ if (errnoval) {
+ r = asprintf(&fmt_free, "%s: %%m", fmt);
+ if (r) {
+ fmt_free = 0;
+ } else {
+ fmt_use = fmt_free;
+ }
+ }
+ vsyslog(LOG_ERR, fmt_use, al);
+ free(fmt_free);
+ } else {
+ fputs("cgi-fcgi-interp: ",stderr);
+ vfprintf(stderr,fmt,al);
+ if (errnoval!=-1) fprintf(stderr,": %s",strerror(errnoval));
+ fputc('\n',stderr);
+ }
+ if (estatus) exit(estatus);
}
+#define DEF_MSG(func, attrs, estatus, errnoval, after) \
+ static void func(const char *fmt, ...) \
+ __attribute__((format(printf,1,2))) attrs; \
+ static void func(const char *fmt, ...) { \
+ va_list al; \
+ va_start(al,fmt); \
+ vmsgcore(estatus,errnoval,fmt,al); \
+ after \
+ }
+
+DEF_MSG(warninge, /*empty*/, 0, errno, { });
+DEF_MSG(warning , /*empty*/, 0, 0, { });
+
+#define DEF_DIE(func, errnoval) \
+ DEF_MSG(func, __attribute__((noreturn)), 127, errnoval, { abort(); })
+
+DEF_DIE(diee, errno)
+DEF_DIE(die, 0)
+
+void common_diee(const char *m) { diee("%s", m); }
+void common_die (const char *m) { die ("%s", m); }
+
static void fusagemessage(FILE *f) {
fprintf(f, "usage: #!/usr/bin/cgi-fcgi-interp [<options>]\n");
}
sha256_update(&identsc,strlen(string)+1,string);
}
+static void off_ident_addenv(const struct cmdinfo *ci, const char *name) {
+ const char *val = getenv(name);
+ if (val) {
+ sha256_update(&identsc,strlen(name),name); /* no nul */
+ sha256_update(&identsc,1,"=");
+ ident_addstring(0,val);
+ } else {
+ ident_addstring(0,name);
+ }
+}
+
#define MAX_OPTS 5
static const struct cmdinfo cmdinfos[]= {
- { "help", 0, .call= of_help },
- { 0, 'g', 1, .sassignto= &ident },
- { 0, 'M', 1, .call=of_iassign, .iassignto= &numservers },
- { 0, 'D', 0, .iassignto= &debugmode, .arg= 1 },
- { 0, 'c', 1, .call=of_iassign, .iassignto= &check_interval },
+ { "help", 0, .call=of_help },
+ { 0, 'g', 1, .sassignto= &ident },
+ { 0, 'G', 1, .call= ident_addstring },
+ { 0, 'E', 1, .call= off_ident_addenv },
+ { 0, 'M', 1, .call=of_iassign, .iassignto= &numservers },
+ { 0, 'D', 0, .iassignto= &debugmode, .arg= 1 },
+ { 0, 'c', 1, .call=of_iassign, .iassignto= &check_interval },
{ 0 }
};
diee("stat /var/run/user/UID");
}
if (!S_ISDIR(stab.st_mode)) {
- warnx("%s not a directory, falling back to ~\n", try);
+ warning("%s not a directory, falling back to ~\n", try);
return 0;
}
if (stab.st_uid != us) {
- warnx("%s not owned by uid %lu, falling back to ~\n", try,
- (unsigned long)us);
+ warning("%s not owned by uid %lu, falling back to ~\n", try,
+ (unsigned long)us);
return 0;
}
if (stab.st_mode & 0077) {
- warnx("%s writeable by group or other, falling back to ~\n", try);
+ warning("%s writeable by group or other, falling back to ~\n", try);
return 0;
}
run_base = m_asprintf("%s/%s", try, "cgi-fcgi-interp");
ut.nodename[32] = 0;
run_base_mkdir_p = m_asprintf("%s/%s", pw->pw_dir, ".cgi-fcgi-interp");
- try = m_asprintf("%/%s", run_base_mkdir_p, ut.nodename);
+ try = m_asprintf("%s/%s", run_base_mkdir_p, ut.nodename);
run_base = try;
return 1;
}
if (!ident) {
if (maxidentlen < MINHEXHASH)
- errx(127,"base directory `%s'"
- " leaves only %d characters for id hash"
- " which is too little (<%d)",
- run_base, maxidentlen, MINHEXHASH);
+ die("base directory `%s'"
+ " leaves only %d characters for id hash"
+ " which is too little (<%d)",
+ run_base, maxidentlen, MINHEXHASH);
int identlen = maxidentlen > 64 ? 64 : maxidentlen;
char *hexident = xmalloc(identlen + 2);
}
if (strlen(ident) > maxidentlen)
- errx(127, "base directory `%s' plus ident `%s' too long"
- " (with spare) for socket (max ident %d)\n",
- run_base, ident, maxidentlen);
+ die("base directory `%s' plus ident `%s' too long"
+ " (with spare) for socket (max ident %d)\n",
+ run_base, ident, maxidentlen);
r = mkdir(run_base, 0700);
if (r && errno==ENOENT && run_base_mkdir_p) {
r = mkdir(run_base_mkdir_p, 0700);
- if (r) err(127,"mkdir %s (since %s was ENOENT)",run_base_mkdir_p,run_base);
+ if (r) diee("mkdir %s (since %s was ENOENT)",run_base_mkdir_p,run_base);
r = mkdir(run_base, 0700);
}
if (r) {
if (!(errno == EEXIST))
- err(127,"mkdir %s",run_base);
+ diee("mkdir %s",run_base);
}
socket_path = m_asprintf("%s/s%s",run_base,ident);
static void stab_mtimenow(struct stat *out) {
int r = clock_gettime(CLOCK_REALTIME, &out->st_mtim);
- if (r) err(127,"(stage2) clock_gettime");
+ if (r) diee("(stage2) clock_gettime");
if (debugmode)
fprintf(stderr,"stab_mtimenow mtim %lu.%06lu\n",
(unsigned long)out->st_mtim.tv_sec,
fprintf(stderr,"stab_isnewer mtime %lu %lu\n",
(unsigned long)a->st_mtime,
(unsigned long)b->st_mtime);
- return a->st_mtime > &b->st_mtime;
+ return a->st_mtime > b->st_mtime;
}
static void stab_mtimenow(struct stat *out) {
out->st_mtime = time(NULL);
- if (baseline_time.st_mtime == (time_t)-1) err(127,"(stage2) time()");
+ if (out->st_mtime == (time_t)-1) diee("(stage2) time()");
if (debugmode)
fprintf(stderr,"stab_mtimenow mtime %lu\n",
(unsigned long)out->st_mtime);
int r;
r = lstat(script, &script_stab);
- if (r) err(127,"lstat script (%s)",script);
+ if (r) diee("lstat script (%s)",script);
if (stab_isnewer(&script_stab, started))
return 1;
if (S_ISLNK(script_stab.st_mode)) {
r = stat(script, &script_stab);
- if (r) err(127,"stat script (%s0",script);
+ if (r) diee("stat script (%s0",script);
if (stab_isnewer(&script_stab, started))
return 1;
if (r) {
if ((errno == ENOENT))
return 0; /* well, no garbage then */
- err(127,"stat socket (%s)",socket_path);
+ diee("stat socket (%s)",socket_path);
}
return check_garbage_vs(&sock_stab);
const char *lock_path = m_asprintf("%s/l%s",run_base,ident);
lockfd = open(lock_path, O_CREAT|O_RDWR, 0600);
- if (lockfd<0) err(127,"create lock (%s)", lock_path);
+ if (lockfd<0) diee("create lock (%s)", lock_path);
r = flock(lockfd, LOCK_EX);
- if (r) err(127,"lock lock (%s)", lock_path);
+ if (r) diee("lock lock (%s)", lock_path);
if (check_garbage()) {
r = unlink(socket_path);
if (r) {
if (!(errno == ENOENT))
- err(127,"remove out-of-date socket (%s)", socket_path);
+ diee("remove out-of-date socket (%s)", socket_path);
}
}
r = close(lockfd);
- if (r) errx(127,"close lock (%s)", lock_path);
+ if (r) diee("close lock (%s)", lock_path);
}
static void make_stderr_copy(void) {
stderr_copy = dup(2);
- if (stderr_copy < 0) err(127,"dup stderr (for copy for stage2)");
+ if (stderr_copy < 0) diee("dup stderr (for copy for stage2)");
}
static void prep_stage2(void) {
const char *stage2_val = m_asprintf("%d", stderr_copy);
r = setenv(STAGE2_VAR, stage2_val, 1);
- if (r) err(127,"set %s (to announce to stage2)", STAGE2_VAR);
+ if (r) diee("set %s (to announce to stage2)", STAGE2_VAR);
}
static void shbang_opts(const char *const **argv_io,
myopt(argv_io, cmdinfos);
interp = *(*argv_io)++;
- if (!interp) errx(127,"need interpreter argument");
+ if (!interp) badusage("need interpreter argument");
}
/* stage2 predeclarations */
static void setup_handlers(void);
static void spawn_script(void);
static void queue_alarm(void);
+static void start_logging(void);
static void await_something(void);
int main(int argc, const char *const *argv) {
assert(r==2);
r = open("/dev/null",O_WRONLY);
- if (r<0) err(127,"open /dev/null as stdout");
+ if (r<0) diee("open /dev/null as stdout");
if (r>=3) close(r);
- else if (r!=1) errx(127,"open /dev/null for stdout gave bad fd %d",r);
+ else if (r!=1) die("open /dev/null for stdout gave bad fd %d",r);
+
+ r = close(stderrfd);
+ if (r) diee("close saved stderr fd");
}
sha256_init(&identsc);
int split_argc = 0;
split_args[split_argc++] = argv[0];
for (;;) {
- if (split_argc >= MAX_OPTS) errx(127,"too many options in combined arg");
+ if (split_argc >= MAX_OPTS) die("too many options in combined arg");
split_args[split_argc++] = smashedopt;
if (smashedopt[0] != '-') /* never true on first iteration */
break;
char *delim = strchr(smashedopt,' ');
if (!delim) delim = strchr(smashedopt,',');
- if (!delim)
- errx(127,"combined arg lacks <interpreter>");
+ if (!delim) badusage("combined arg lacks <interpreter>");
*delim = 0;
smashedopt = delim+1;
}
shbang_opts(&split_argv, cmdinfos);
/* sets interp */
- if (!split_argv) errx(127,"combined arg too many non-option arguments");
+ if (!split_argv) badusage("combined arg too many non-option arguments");
} else {
shbang_opts(&argv, cmdinfos);
}
script = *argv++;
- if (!script) errx(127,"need script argument");
- if (*argv) errx(127,"too many arguments");
+ if (!script) badusage("need script argument");
if (!stage2) {
script,
m_asprintf("%d", numservers),
(char*)0);
- err(127,"exec cgi-fcgi");
+ diee("exec cgi-fcgi");
} else { /*stage2*/
setup_handlers();
spawn_script();
queue_alarm();
+ start_logging();
await_something();
abort();
static struct stat baseline_time;
static pid_t script_child, stage2_pgrp;
static bool out_of_date;
+static int errpipe;
static void record_baseline_time(void) {
stab_mtimenow(&baseline_time);
stage2_pgrp = getpid();
r = setpgid(0,0);
- if (r) err(127,"(stage2) setpgid");
+ if (r) diee("(stage2) setpgid");
}
static void atexit_handler(void) {
int r;
sighandler_t sigr = signal(SIGTERM,SIG_IGN);
- if (sigr == SIG_ERR) warn("(stage2) signal(SIGTERM,SIG_IGN)");
+ if (sigr == SIG_ERR) warninge("(stage2) signal(SIGTERM,SIG_IGN)");
r = killpg(stage2_pgrp,SIGTERM);
- if (r) warn("(stage) killpg failed");
+ if (r) warninge("(stage) killpg failed");
}
static void alarm_handler(int dummy) {
for (;;) {
int status;
pid_t got = waitpid(-1, &status, WNOHANG);
- if (got == (pid_t)-1) err(127,"(stage2) waitpid");
+ if (got == (pid_t)-1) diee("(stage2) waitpid");
if (got != script_child) {
- warn("(stage2) waitpid got status %d for unknown child [%lu]",
- status, (unsigned long)got);
+ warning("(stage2) waitpid got status %d for unknown child [%lu]",
+ status, (unsigned long)got);
continue;
}
if (WIFEXITED(status)) {
int v = WEXITSTATUS(status);
- if (v) warn("program failed with error exit status %d", v);
+ if (v) warning("program failed with error exit status %d", v);
exit(status);
} else if (WIFSIGNALED(status)) {
int s = WTERMSIG(status);
- err(status & 0xff, "program died due to fatal signal %s%s",
- strsignal(s), WCOREDUMP(status) ? " (core dumped" : "");
+ warning("program died due to fatal signal %s%s",
+ strsignal(s), WCOREDUMP(status) ? " (core dumped" : "");
+ assert(status & 0xff);
+ exit(status & 0xff);
} else {
- err(127, "program failed with crazy wait status %#x", status);
+ die("program failed with crazy wait status %#x", status);
}
}
exit(127);
int r;
r = atexit(atexit_handler);
- if (r) err(127,"(stage2) atexit");
+ if (r) diee("(stage2) atexit");
sigemptyset(&sa.sa_mask);
sigaddset(&sa.sa_mask, SIGALRM);
sa.sa_flags = 0;
r = sigprocmask(SIG_BLOCK, &sa.sa_mask, 0);
- if (r) err(127,"(stage2) sigprocmask(SIG_BLOCK,)");
+ if (r) diee("(stage2) sigprocmask(SIG_BLOCK,)");
sa.sa_handler = alarm_handler;
r = sigaction(SIGALRM, &sa, 0);
- if (r) err(127,"(stage2) sigaction SIGALRM");
+ if (r) diee("(stage2) sigaction SIGALRM");
sa.sa_flags |= SA_NOCLDSTOP;
sa.sa_handler = child_handler;
r = sigaction(SIGCHLD, &sa, 0);
- if (r) err(127,"(stage2) sigaction SIGCHLD");
+ if (r) diee("(stage2) sigaction SIGCHLD");
}
static void spawn_script(void) {
+ int r;
+ int errpipes[2];
+
+ r = pipe(errpipes);
+ if (r) diee("(stage2) pipe");
+
script_child = fork();
- if (script_child == (pid_t)-1) err(127,"(stage2) fork");
+ if (script_child == (pid_t)-1) diee("(stage2) fork");
if (!script_child) {
+ r = close(errpipes[0]);
+ if (r) diee("(stage2 child) close errpipes[0]");
+
+ r = dup2(errpipes[1], 2);
+ if (r != 2) diee("(stage2 child) dup2 stderr");
+
execlp(interp,
interp, script, (char*)0);
- err(127,"(stage2) exec interpreter (`%s', for `%s')\n",interp,script);
+ diee("(stage2) exec interpreter (`%s', for `%s')\n",interp,script);
}
+
+ r = close(errpipes[1]);
+ if (r) diee("(stage2) close errpipes[1]");
+
+ errpipe = errpipes[0];
+ r = fcntl(errpipe, F_SETFL, O_NONBLOCK);
+ if (r) diee("(stage2) set errpipe nonblocking");
}
static void queue_alarm(void) {
alarm(check_interval);
}
+static void start_logging(void) {
+ int r;
+
+ openlog(script, LOG_NOWAIT|LOG_PID, LOG_USER);
+ logging = 1;
+ r = dup2(1,2);
+ if (r!=2) diee("dup2 stdout to stderr");
+}
+
+static void errpipe_readable(void) {
+ static char buf[1024];
+ static int pending;
+
+ /* %: does not contain newlines
+ * _: empty (garbage)
+ */
+
+ /* %%%%%%%%%%%__________________ */
+ /* ^ pending */
+
+ for (;;) {
+ int avail = sizeof(buf) - pending;
+ ssize_t got = read(errpipe, buf+pending, avail);
+ if (got==-1) {
+ if (errno==EINTR) continue;
+ else if (errno==EWOULDBLOCK || errno==EAGAIN) return;
+ else diee("(stage2) errpipe read");
+ got = 0;
+ } else if (got==0) {
+ warning("program closed its stderr fd");
+ errpipe = -1;
+ return;
+ }
+ int scanned = pending;
+ pending += got;
+ int eaten = 0;
+ for (;;) {
+ const char *newline = memchr(buf+scanned, '\n', pending-scanned);
+ int printupto, eat;
+ if (newline) {
+ printupto = newline-buf;
+ eat = printupto + 1;
+ } else if (!eaten && pending==sizeof(buf)) { /* overflow */
+ printupto = pending;
+ eat = printupto;
+ } else {
+ break;
+ }
+ syslog(LOG_ERR,"stderr: %.*s", printupto-eaten, buf+eaten);
+ eaten += eat;
+ scanned = eaten;
+ }
+ pending -= eaten;
+ memmove(buf, buf+eaten, pending);
+ }
+}
+
static void await_something(void) {
int r;
sigset_t mask;
sigemptyset(&mask);
for (;;) {
- r = sigsuspend(&mask);
- assert(r==-1);
- if (errno != EINTR) err(127,"(stage2) sigsuspend");
+ fd_set rfds;
+ FD_ZERO(&rfds);
+ if (errpipe >= 0)
+ FD_SET(errpipe, &rfds);
+ r = pselect(errpipe+1, &rfds,0,0, 0, &mask);
+ if (r==-1) {
+ if (errno != EINTR) diee("(stage2) sigsuspend");
+ continue;
+ }
+ assert(r>0);
+ assert(FD_ISSET(errpipe, &rfds));
+ errpipe_readable();
}
}
~ian / chiark-utils.git / blobdiff