Use proc_open() instead of exec() for runing git commands

shell_exec() could be used instead, but proc_open() has the added
benefit
of runing commands directly (if passed as array), without forking a
shell.
Also, shell_exec returns only the command output, and there is no way to
capture return codes.
This commit is contained in:
Marcos de Oliveira 2021-05-04 10:27:31 -03:00 committed by Andreas Shimokawa
parent 2266db03b7
commit 523b5f052c
1 changed files with 64 additions and 24 deletions

View File

@ -148,10 +148,56 @@ $file_url = implode("/", $request_url_parts);
if (substr($git_root, 0, strlen($git_prefix)) !== $git_prefix)
send_response(404, "this user/organization does not have codeberg pages");
# Setup file descriptors
$null_fd = array(
1 => array('file','/dev/null','w'),
2 => array('file','/dev/null','w'),
);
$pipe_fd = array(
1 => array('pipe','w'),
2 => array('pipe','w'),
);
/**
* Excute git commands
* @param string $cmd_array git command to be executed
* @param string &$stdout reference to $stdout variable, to receive stdout value
* @param string &$stderr reference to $stderr variable, to receive stderr value
* @param string &$retval reference to $retval variable, to receive return value
*/
function git_exec($cmd_array, &$stdout = false, &$retval = false, &$stderr = false) {
global $git_root, $pipe_fd;
$git_bin = '/usr/bin/git';
array_unshift($cmd_array, $git_bin);
$process = proc_open($cmd_array, $pipe_fd, $pipes, $git_root);
if($stdout !== false)
$stdout = stream_get_contents($pipes[1]);
if($stderr !== false)
$stderr = stream_get_contents($pipes[2]);
fclose($pipes[1]);
fclose($pipes[2]);
$tmpret = proc_close($process);
if($retval !== false)
$retval = $tmpret;
}
/**
* Check whether git command succeeds
* @param string $command git command to be checked
* @return bool true if return value is 0, false otherwise
*/
function git_check($cmd_array) {
global $git_root, $null_fd;
$git_bin = '/usr/bin/git';
array_unshift($cmd_array, $git_bin);
return ( proc_close(proc_open($cmd_array,$null_fd,$pipes,$git_root)) === 0 );
}
# If this is a folder, we explicitly redirect to folder URL, otherwise browsers will construct invalid relative links:
$command = "sh -c \"cd '$git_root' && /usr/bin/git ls-tree 'HEAD:$file_url' > /dev/null\"";
exec($command, $output, $retval);
if ($retval === 0) {
$command = ["ls-tree", "HEAD:$file_url"];
if (git_check($command)) {
if (substr($request_url, -1) !== "/") {
$h = "Location: " . $request_url . "/";
if ($_SERVER['QUERY_STRING'] !== "")
@ -196,10 +242,10 @@ header("Content-Type: " . $mime_type);
#header("Cache-Control: public, max-age=10, immutable");
$command = "sh -c \"cd '$git_root' && /usr/bin/git log --format='%H' -1\"";
exec($command, $output, $retval);
if ($retval == 0 && count($output)) {
$revision=$output[0];
$command = ["log", "--format=%H", "-1"];
git_exec($command, $output, $retval);
if ($retval === 0 && !empty($output)) {
$revision=trim($output);
header('ETag: "' . $revision . '"');
if (isset($_SERVER["HTTP_IF_NONE_MATCH"])) {
$req_revision = str_replace('"', '', str_replace('W/"', '', $_SERVER["HTTP_IF_NONE_MATCH"]));
@ -208,26 +254,20 @@ if ($retval == 0 && count($output)) {
}
}
}
## We are executing command twice (first for send_response-checking, then for actual raw output to stream),
## which seems wasteful, but it seems exec+echo cannot do raw binary output? Is this true?
$command = "sh -c \"cd '$git_root' && /usr/bin/git show 'HEAD:$file_url'\"";
exec($command . " > /dev/null", $output, $retval);
if ($retval != 0) {
$command = ["show", "HEAD:$file_url"];
git_exec($command, $output, $retval);
if ($retval !== 0) {
# Try adding '.html' suffix, if this does not work either, report error
$command = "sh -c \"cd '$git_root' && /usr/bin/git show 'HEAD:$file_url.html'\"";
exec($command . " > /dev/null", $output, $retval);
$command = ["show", "HEAD:$file_url.html"];
git_exec($command, $output, $retval);
header("Content-Type: text/html");
if ($retval != 0) {
if ($retval !== 0) {
# Render user-provided 404.html if exists, generic 404 message if not:
http_response_code(404);
$command = "sh -c \"cd '$git_root' && /usr/bin/git show 'HEAD:404.html'\"";
exec($command . " > /dev/null", $output, $retval);
if ($retval != 0)
send_response(404 , "no such file in repo: '" . htmlspecialchars($file_url) . "'");
$command = ["show", "HEAD:404.html"];
git_exec($command, $output, $retval);
if ($retval !== 0)
send_response(404, "no such file in repo: '" . htmlspecialchars($file_url) . "'");
}
}
## If we could directly exec+echo raw output from above, we wouldn't need to execute command twice:
passthru($command);
echo $output;