mail: fix exit code handling of sendmail cmd

Prior to this commit the return code of the pclose function was assumed
to be the exit code of the process. However, the returned value as
specified in wait(2) is a bit packed integer and must be interpreted
with the provided macros. After this commit we use the macros to obtain
the status code and also add some logging on failure.

For WIN32 we only check if the return value is non-zero, which should
solve, #43327

Author: lollipopman

ext/standard/mail.c

@@ -25,6 +25,10 @@
 #include "ext/date/php_date.h"
 #include "zend_smart_str.h"
 
+#ifdef HAVE_SYS_WAIT_H
+#include <sys/wait.h>
+#endif
+
 #ifdef HAVE_SYSEXITS_H
 # include <sysexits.h>
 #endif
@@ -417,6 +421,7 @@ PHPAPI int php_mail(const char *to, const char *subject, const char *message, co
 #endif
 	FILE *sendmail;
 	int ret;
+	int wstatus;
 	char *sendmail_path = INI_STR("sendmail_path");
 	char *sendmail_cmd = NULL;
 	char *mail_log = INI_STR("mail.log");
@@ -557,26 +562,44 @@ PHPAPI int php_mail(const char *to, const char *subject, const char *message, co
 			fprintf(sendmail, "%s%s", hdr, line_sep);
 		}
 		fprintf(sendmail, "%s%s%s", line_sep, message, line_sep);
+#ifdef PHP_WIN32
 		ret = pclose(sendmail);
-
 #if PHP_SIGCHILD
 		if (sig_handler) {
 			signal(SIGCHLD, sig_handler);
 		}
 #endif
-
-#ifdef PHP_WIN32
-		if (ret == -1)
 #else
+		wstatus = pclose(sendmail);
+#if PHP_SIGCHILD
+		if (sig_handler) {
+			signal(SIGCHLD, sig_handler);
+		}
+#endif
+		/* Determine the wait(2) exit status */
+		if (wstatus == -1) {
+			php_error_docref(NULL, E_WARNING, "Sendmail pclose failed %d (%s)", errno, strerror(errno));
+			MAIL_RET(0);
+		} else if (WIFSIGNALED(wstatus)) {
+			php_error_docref(NULL, E_WARNING, "Sendmail killed by signal %d (%s)", WTERMSIG(wstatus), strsignal(WTERMSIG(wstatus)));
+			MAIL_RET(0);
+		} else if (!WIFEXITED(wstatus)) {
+			php_error_docref(NULL, E_WARNING, "Sendmail did not exit");
+			MAIL_RET(0);
+		} else {
+			ret = WEXITSTATUS(wstatus);
+		}
+#endif
+
 #if defined(EX_TEMPFAIL)
 		if ((ret != EX_OK)&&(ret != EX_TEMPFAIL))
 #elif defined(EX_OK)
 		if (ret != EX_OK)
 #else
 		if (ret != 0)
-#endif
 #endif
 		{
+			php_error_docref(NULL, E_WARNING, "Sendmail exited with non-zero exit code %d", ret);
 			MAIL_RET(0);
 		} else {
 			MAIL_RET(1);

ext/standard/tests/mail/gh10990.phpt

@@ -13,5 +13,6 @@ $from = '[email protected]';
 $headers = ['From' => &$from];
 var_dump(mail('[email protected]', 'Test', 'Test', $headers));
 ?>
---EXPECT--
+--EXPECTF--
+Warning: mail(): Sendmail exited with non-zero exit code 127 in %sgh10990.php on line %d
 bool(false)

ext/standard/tests/mail/mail_basic5.phpt

@@ -20,7 +20,9 @@ $message = 'A Message';
 echo "-- failure --\n";
 var_dump( mail($to, $subject, $message) );
 ?>
---EXPECT--
+--EXPECTF--
 *** Testing mail() : basic functionality ***
 -- failure --
+
+Warning: mail(): Sendmail exited with non-zero exit code 1 in %smail_basic5.php on line %d
 bool(false)

ext/standard/tests/mail/mail_variation1.phpt

@@ -17,6 +17,8 @@ $subject = 'Test Subject';
 $message = 'A Message';
 var_dump( mail($to, $subject, $message) );
 ?>
---EXPECT--
+--EXPECTF--
 *** Testing mail() : variation ***
+
+Warning: mail(): Sendmail exited with non-zero exit code 127 in %smail_variation1.php on line %d
 bool(false)

ext/standard/tests/mail/mail_variation3.phpt

@@ -0,0 +1,22 @@
+--TEST--
+Test mail() function : variation sendmail temp fail
+--INI--
+sendmail_path=exit 75
+--SKIPIF--
+<?php
+if(substr(PHP_OS, 0, 3) == "WIN")
+  die("skip Won't run on Windows");
+?>
+--FILE--
+<?php
+echo "*** Testing mail() : variation ***\n";
+
+// Initialise all required variables
+$to = '[email protected]';
+$subject = 'Test Subject';
+$message = 'A Message';
+var_dump( mail($to, $subject, $message) );
+?>
+--EXPECT--
+*** Testing mail() : variation ***
+bool(true)

ext/standard/tests/mail/mail_variation4.phpt

@@ -0,0 +1,24 @@
+--TEST--
+Test mail() function : variation sigkill
+--INI--
+sendmail_path="kill \$\$"
+--SKIPIF--
+<?php
+if(substr(PHP_OS, 0, 3) == "WIN")
+  die("skip Won't run on Windows");
+?>
+--FILE--
+<?php
+echo "*** Testing mail() : variation ***\n";
+
+// Initialise all required variables
+$to = '[email protected]';
+$subject = 'Test Subject';
+$message = 'A Message';
+var_dump( mail($to, $subject, $message) );
+?>
+--EXPECTF--
+*** Testing mail() : variation ***
+
+Warning: mail(): Sendmail killed by signal %d (%s) in %smail_variation4.php on line %d
+bool(false)