X-Git-Url: http://git.vanrenterghem.biz/git.ikiwiki.info.git/blobdiff_plain/912521ef0711204965aa2319d41c7741bd3f4f4c..142f4e12fcbcf61da536d9ad3b308e4240adb1e0:/IkiWiki/Wrapper.pm

diff --git a/IkiWiki/Wrapper.pm b/IkiWiki/Wrapper.pm
index e761085fb..69500029c 100644
--- a/IkiWiki/Wrapper.pm
+++ b/IkiWiki/Wrapper.pm
@@ -1,17 +1,38 @@
 #!/usr/bin/perl
 
+package IkiWiki;
+
 use warnings;
 use strict;
-use Cwd q{abs_path};
+use File::Spec;
 use Data::Dumper;
 use IkiWiki;
 
-package IkiWiki;
+sub gen_wrappers () {
+	debug(gettext("generating wrappers.."));
+	my %origconfig=(%config);
+	foreach my $wrapper (@{$config{wrappers}}) {
+		%config=(%origconfig, %{$wrapper});
+		$config{verbose}=$config{setupverbose}
+			if exists $config{setupverbose};
+		$config{syslog}=$config{setupsyslog}
+			if exists $config{setupsyslog};
+		delete @config{qw(setupsyslog setupverbose wrappers genwrappers rebuild)};
+		checkconfig();
+		if (! $config{cgi} && ! $config{post_commit} &&
+		    ! $config{test_receive}) {
+			$config{post_commit}=1;
+		}
+		gen_wrapper();
+	}
+	%config=(%origconfig);
+}
 
-sub gen_wrapper () { #{{{
-	$config{srcdir}=abs_path($config{srcdir});
-	$config{destdir}=abs_path($config{destdir});
-	my $this=abs_path($0);
+our $program_to_wrap = $0;
+sub gen_wrapper () {
+	$config{srcdir}=File::Spec->rel2abs($config{srcdir});
+	$config{destdir}=File::Spec->rel2abs($config{destdir});
+	my $this=File::Spec->rel2abs($program_to_wrap);
 	if (! -x $this) {
 		error(sprintf(gettext("%s doesn't seem to be executable"), $this));
 	}
@@ -28,80 +49,263 @@ sub gen_wrapper () { #{{{
 	my @envsave;
 	push @envsave, qw{REMOTE_ADDR QUERY_STRING REQUEST_METHOD REQUEST_URI
 	               CONTENT_TYPE CONTENT_LENGTH GATEWAY_INTERFACE
-		       HTTP_COOKIE REMOTE_USER} if $config{cgi};
+		       HTTP_COOKIE REMOTE_USER HTTPS REDIRECT_STATUS
+		       HTTP_HOST SERVER_PORT HTTPS HTTP_ACCEPT
+		       REDIRECT_URL} if $config{cgi};
+	my $envsize=$#envsave;
 	my $envsave="";
 	foreach my $var (@envsave) {
-		$envsave.=<<"EOF"
+		$envsave.=<<"EOF";
 	if ((s=getenv("$var")))
-		asprintf(&newenviron[i++], "%s=%s", "$var", s);
+		addenv("$var", s);
 EOF
 	}
-	if ($config{rcs} eq "svn" && $config{notify}) {
-		# Support running directly as hooks/post-commit by passing
-		# $2 in REV in the environment.
-		$envsave.=<<"EOF"
-	if (argc == 3)
-		asprintf(&newenviron[i++], "REV=%s", argv[2]);
-	else if ((s=getenv("REV")))
-		asprintf(&newenviron[i++], "%s=%s", "REV", s);
+	if (ref $config{ENV} eq 'HASH') {
+		foreach my $key (keys %{$config{ENV}}) {
+			my $val=$config{ENV}{$key};
+			utf8::encode($val) if utf8::is_utf8($val);
+			$val =~ s/([^A-Za-z0-9])/sprintf '""\\x%02x""', ord($1)/ge;
+			$envsize += 1;
+			$envsave.=<<"EOF";
+	addenv("$key", "$val");
 EOF
+		}
+		delete $config{ENV};
+	}
+	
+	my @wrapper_hooks;
+	run_hooks(genwrapper => sub { push @wrapper_hooks, shift->() });
+
+	my $check_commit_hook="";
+	my $pre_exec="";
+	if ($config{post_commit}) {
+		# Optimise checking !commit_hook_enabled() , 
+		# so that ikiwiki does not have to be started if the
+		# hook is disabled.
+		#
+		# Note that perl's flock may be implemented using fcntl
+		# or lockf on some systems. If so, and if there is no
+		# interop between the locking systems, the true C flock will
+		# always succeed, and this optimisation won't work.
+		# The perl code will later correctly check the lock,
+		# so the right thing will still happen, though without
+		# the benefit of this optimisation.
+		$check_commit_hook=<<"EOF";
+	{
+		int fd=open("$config{wikistatedir}/commitlock", O_CREAT | O_RDWR, 0666);
+		if (fd != -1) {
+			if (flock(fd, LOCK_SH | LOCK_NB) != 0)
+				exit(0);
+			close(fd);
+		}
 	}
-	if ($config{rcs} eq "tla" && $config{notify}) {
-		$envsave.=<<"EOF"
-	if ((s=getenv("ARCH_VERSION")))
-		asprintf(&newenviron[i++], "%s=%s", "ARCH_VERSION", s);
 EOF
 	}
-	
+	elsif ($config{cgi}) {
+		# Avoid more than one ikiwiki cgi running at a time by
+		# taking a cgi lock. Since ikiwiki uses several MB of
+		# memory, a pile up of processes could cause thrashing
+		# otherwise. The fd of the lock is stored in
+		# IKIWIKI_CGILOCK_FD so unlockwiki can close it.
+		#
+		# A lot of cgi wrapper processes can potentially build
+		# up and clog an otherwise unloaded web server. To
+		# partially avoid this, when a GET comes in and the lock
+		# is already held, rather than blocking a html page is
+		# constructed that retries. This is enabled by setting
+		# cgi_overload_delay.
+		if (defined $config{cgi_overload_delay} &&
+		    $config{cgi_overload_delay} =~/^[0-9]+/) {
+			my $i=int($config{cgi_overload_delay});
+			$pre_exec.="#define CGI_OVERLOAD_DELAY $i\n"
+				if $i > 0;
+			my $msg=gettext("Please wait");
+			$msg=~s/"/\\"/g;
+			$pre_exec.='#define CGI_PLEASE_WAIT_TITLE "'.$msg."\"\n";
+			if (defined $config{cgi_overload_message} && length $config{cgi_overload_message}) {
+				$msg=$config{cgi_overload_message};
+				$msg=~s/"/\\"/g;
+			}
+			$pre_exec.='#define CGI_PLEASE_WAIT_BODY "'.$msg."\"\n";
+		}
+		$pre_exec.=<<"EOF";
+	lockfd=open("$config{wikistatedir}/cgilock", O_CREAT | O_RDWR, 0666);
+	if (lockfd != -1) {
+#ifdef CGI_OVERLOAD_DELAY
+		char *request_method = getenv("REQUEST_METHOD");
+		if (request_method && strcmp(request_method, "GET") == 0) {
+			if (lockf(lockfd, F_TLOCK, 0) == 0) {
+				set_cgilock_fd(lockfd);
+			}
+			else {
+				printf("Content-Type: text/html\\nRefresh: %i; URL=%s\\n\\n<html><head><title>%s</title><head><body><p>%s</p></body></html>",
+					CGI_OVERLOAD_DELAY,
+					getenv("REQUEST_URI"),
+					CGI_PLEASE_WAIT_TITLE,
+					CGI_PLEASE_WAIT_BODY);
+				exit(0);
+			}
+		}
+		else if (lockf(lockfd, F_LOCK, 0) == 0) {
+			set_cgilock_fd(lockfd);
+		}
+#else
+		if (lockf(lockfd, F_LOCK, 0) == 0) {
+			set_cgilock_fd(lockfd);
+		}
+#endif
+	}
+EOF
+	}
+
+	my $set_background_command='';
+	if (defined $config{wrapper_background_command} &&
+	    length $config{wrapper_background_command}) {
+	    	my $background_command=delete $config{wrapper_background_command};
+		$set_background_command=~s/"/\\"/g;
+		$set_background_command='#define BACKGROUND_COMMAND "'.$background_command.'"';
+	}
+
 	$Data::Dumper::Indent=0; # no newlines
 	my $configstring=Data::Dumper->Dump([\%config], ['*config']);
 	$configstring=~s/\\/\\\\/g;
 	$configstring=~s/"/\\"/g;
-	$configstring=~s/\n/\\\n/g;
+	$configstring=~s/\n/\\n/g;
 	
-	open(OUT, ">$wrapper.c") || error(sprintf(gettext("failed to write %s: %s"), "$wrapper.c", $!));;
-	print OUT <<"EOF";
+	writefile(basename("$wrapper.c"), dirname($wrapper), <<"EOF");
 /* A wrapper for ikiwiki, can be safely made suid. */
-#define _GNU_SOURCE
 #include <stdio.h>
 #include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
 #include <unistd.h>
 #include <stdlib.h>
 #include <string.h>
+#include <sys/file.h>
 
 extern char **environ;
+char *newenviron[$envsize+7];
+int i=0;
+
+void addenv(char *var, char *val) {
+	char *s=malloc(strlen(var)+1+strlen(val)+1);
+	if (!s) {
+		perror("malloc");
+		exit(1);
+	}
+	else {
+		sprintf(s, "%s=%s", var, val);
+		newenviron[i++]=s;
+	}
+}
+
+void set_cgilock_fd (int lockfd) {
+	char fd_s[12];
+	sprintf(fd_s, "%i", lockfd);
+	if (setenv("IKIWIKI_CGILOCK_FD", fd_s, 1) != 0) {
+		perror("setenv");
+		exit(1);
+	}
+}
 
 int main (int argc, char **argv) {
-	/* Sanitize environment. */
+	int lockfd=-1;
 	char *s;
-	char *newenviron[$#envsave+5];
-	int i=0;
+
+$check_commit_hook
+@wrapper_hooks
 $envsave
 	newenviron[i++]="HOME=$ENV{HOME}";
+	newenviron[i++]="PATH=$ENV{PATH}";
 	newenviron[i++]="WRAPPED_OPTIONS=$configstring";
+
+#ifdef __TINYC__
+	/* old tcc versions do not support modifying environ directly */
+	if (clearenv() != 0) {
+		perror("clearenv");
+		exit(1);
+	}
+	for (; i>0; i--)
+		putenv(newenviron[i-1]);
+#else
 	newenviron[i]=NULL;
 	environ=newenviron;
+#endif
 
-	if (setregid(getegid(), -1) != 0 || setreuid(geteuid(), -1) != 0) {
-		perror("failed to drop real uid/gid");
+	if (setregid(getegid(), -1) != 0 &&
+	    setregid(getegid(), -1) != 0) {
+		perror("failed to drop real gid");
+		exit(1);
+	}
+	if (setreuid(geteuid(), -1) != 0 &&
+	    setreuid(geteuid(), -1) != 0) {
+		perror("failed to drop real uid");
 		exit(1);
 	}
 
+$pre_exec
+
+$set_background_command
+#ifdef BACKGROUND_COMMAND
+	if (lockfd != -1) {
+		close(lockfd);
+	}
+
+	pid_t pid=fork();
+	if (pid == -1) {
+		perror("fork");
+		exit(1);
+	}
+	else if (pid == 0) {
+		execl("$this", "$this", NULL);
+		perror("exec $this");
+		exit(1);		
+	}
+	else {
+		waitpid(pid, NULL, 0);
+
+		if (daemon(1, 0) == 0) {
+			system(BACKGROUND_COMMAND);
+			exit(0);
+		}
+		else {
+			perror("daemon");
+			exit(1);
+		}
+	}
+#else
 	execl("$this", "$this", NULL);
-	perror("failed to run $this");
+	perror("exec $this");
 	exit(1);
+#endif
 }
 EOF
-	close OUT;
-	if (system("gcc", "$wrapper.c", "-o", $wrapper) != 0) {
+
+	my @cc=exists $ENV{CC} ? possibly_foolish_untaint($ENV{CC}) : 'cc';
+	push @cc, split(' ', possibly_foolish_untaint($ENV{CFLAGS})) if exists $ENV{CFLAGS};
+	if (system(@cc, "$wrapper.c", "-o", "$wrapper.new") != 0) {
+		#translators: The parameter is a C filename.
 		error(sprintf(gettext("failed to compile %s"), "$wrapper.c"));
 	}
 	unlink("$wrapper.c");
+	if (defined $config{wrappergroup}) {
+		my $gid=(getgrnam($config{wrappergroup}))[2];
+		if (! defined $gid) {
+			error(sprintf("bad wrappergroup"));
+		}
+		if (! chown(-1, $gid, "$wrapper.new")) {
+			error("chown $wrapper.new: $!");
+		}
+	}
 	if (defined $config{wrappermode} &&
-	    ! chmod(oct($config{wrappermode}), $wrapper)) {
-		error("chmod $wrapper: $!");
+	    ! chmod(oct($config{wrappermode}), "$wrapper.new")) {
+		error("chmod $wrapper.new: $!");
 	}
-	printf(gettext("successfully generated %s\n"), $wrapper);
-} #}}}
+	if (! rename("$wrapper.new", $wrapper)) {
+		error("rename $wrapper.new $wrapper: $!");
+	}
+	#translators: The parameter is a filename.
+	debug(sprintf(gettext("successfully generated %s"), $wrapper));
+}
 
 1