standard: Remove php_std_date() C API (php#18522)

This function is unused and trivially replaced by `php_format_date()` (which is
already used to format date headers in the CLI server and ext/session). Remove
it to slim down the codebase, allowing to remove an entire header (and a source
file once the deprecated `strptime()` userland function is removed).

Author: TimWolla

UPGRADING.INTERNALS

@@ -64,6 +64,8 @@ PHP 8.5 INTERNALS UPGRADE NOTES
 - ext/standard
   . Added php_url_decode_ex() and php_raw_url_decode_ex() that unlike their
     non-ex counterparts do not work in-place.
+  . The php_std_date() function has been removed. Use php_format_date() with
+    the "D, d M Y H:i:s \\G\\M\\T" format instead.
 
 ========================
 4. OpCode changes

ext/standard/datetime.c

@@ -17,50 +17,12 @@
  */
 
 #include "php.h"
-#include "zend_operators.h"
-#include "datetime.h"
 #include "php_globals.h"
 
 #include <time.h>
 #ifdef HAVE_SYS_TIME_H
 # include <sys/time.h>
 #endif
-#include <stdio.h>
-
-static const char * const mon_short_names[] = {
-	"Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"
-};
-
-static const char * const day_short_names[] = {
-	"Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"
-};
-
-/* {{{ PHPAPI char *php_std_date(time_t t)
-   Return date string in standard format for http headers */
-PHPAPI char *php_std_date(time_t t)
-{
-	struct tm *tm1, tmbuf;
-	char *str;
-
-	tm1 = php_gmtime_r(&t, &tmbuf);
-	str = emalloc(81);
-	str[0] = '\0';
-
-	if (!tm1) {
-		return str;
-	}
-
-	snprintf(str, 80, "%s, %02d %s %04d %02d:%02d:%02d GMT",
-			day_short_names[tm1->tm_wday],
-			tm1->tm_mday,
-			mon_short_names[tm1->tm_mon],
-			tm1->tm_year + 1900,
-			tm1->tm_hour, tm1->tm_min, tm1->tm_sec);
-
-	str[79] = 0;
-	return (str);
-}
-/* }}} */
 
 #ifdef HAVE_STRPTIME
 #ifndef HAVE_DECL_STRPTIME

ext/standard/datetime.h

@@ -30,7 +30,6 @@
 #include "php_filestat.h"
 #include "php_browscap.h"
 #include "pack.h"
-#include "datetime.h"
 #include "url.h"
 #include "pageinfo.h"
 #include "fsock.h"