Add option to set the modification date/time

This also adds an API function for getting an Unix timestamp
(and updates the man page)

lib/file.c

@@ -987,6 +987,21 @@ bool unshield_file_iso_date (Unshield* unshield, int index, char* buf, size_t si
   return fd ? true : false;
 }/*}}}*/
 
+time_t unshield_file_timestamp (Unshield* unshield, int index)/*{{{*/
+{
+  FileDescriptor* fd = unshield_get_file_descriptor(unshield, index);
+  struct tm date;
+
+  if (fd)
+  {
+    unshield_dos_to_tm(fd->dos_date, fd->dos_time, &date);
+    return mktime(&date);
+  }
+
+  unshield_warning("Failed to get file descriptor %i", index);
+  return 0;
+}/*}}}*/
+
 bool unshield_file_save_raw(Unshield* unshield, int index, const char* filename)
 {
   /* XXX: Thou Shalt Not Cut & Paste... */

lib/libunshield.h

@@ -110,6 +110,7 @@ UNSHIELD_API bool        unshield_file_save          (Unshield* unshield, int in
 UNSHIELD_API int         unshield_file_directory     (Unshield* unshield, int index);
 UNSHIELD_API size_t      unshield_file_size          (Unshield* unshield, int index);
 UNSHIELD_API bool        unshield_file_iso_date      (Unshield* unshield, int index, char* buf, size_t size);
+UNSHIELD_API time_t      unshield_file_timestamp     (Unshield* unshield, int index);
 
 /** For investigation of compressed data */
 UNSHIELD_API bool unshield_file_save_raw(Unshield* unshield, int index, const char* filename);

man/unshield.1

@@ -1,8 +1,8 @@
-.TH UNSHIELD "1" "November 2023" "The Unshield project" "https://github.com/twogood/unshield"
+.TH UNSHIELD "1" "December 2024" "The Unshield project" "https://github.com/twogood/unshield"
 .SH NAME
 unshield \- extract CAB files from an InstallShield installer archive
 .SH SYNOPSIS
-unshield [\-c COMPONENT] [\-d DIRECTORY] [\-D LEVEL] [\-g GROUP] [\-h] [\-i VERSION] [\-e ENCODING] [\-j] [\-L] [\-O] [\-r] [\-R] [\-V] c|g|l|t|x CABFILE [FILENAME...]
+unshield [\-c COMPONENT] [\-d DIRECTORY] [\-D LEVEL] [\-g GROUP] [\-h] [\-i VERSION] [\-e ENCODING] [\-j] [\-L] [\-O] [\-r] [\-R] [\-t] [\-V] c|g|l|t|x CABFILE [FILENAME...]
 .SH DESCRIPTION
 Unshield extracts CAB files from InstallShield installers, used to 
 install software on Microsoft Windows based machines.
@@ -50,6 +50,9 @@ Save raw data (do not decompress)
 \fB\-R\fR
 Don't do any conversion to file and directory names when extracting
 .TP
+\fB-t\fR
+Set the modification date/time from the metadata when extracting
+.TP
 \fB\-V\fR, \fB\-\-version\fR
 Print version information
 .SS "Commands:"

src/unshield.c

@@ -11,6 +11,7 @@
 #include <stdlib.h>
 #include <string.h>
 #include <unistd.h>
+#include <utime.h>
 #include <getopt.h>
 #include "../lib/libunshield.h"
 #ifdef HAVE_CONFIG_H
@@ -68,6 +69,7 @@ static const char* component_name     = NULL;
 static bool junk_paths                = false;
 static bool make_lowercase            = false;
 static bool raw_filename              = false;
+static bool set_timestamp             = false;
 static ACTION action                  = ACTION_EXTRACT;
 static int log_level                  = UNSHIELD_LOG_LEVEL_LOWEST;
 static int exit_status                = 0;
@@ -192,7 +194,7 @@ static void show_usage(const char* name)
   fprintf(stderr,
       "Syntax:\n"
       "\n"
-      "\t%s [-c COMPONENT] [-d DIRECTORY] [-D LEVEL] [-g GROUP] [-h] [-i VERSION] [-e ENCODING] [-j] [-L] [-O] [-r] [-R] [-V] c|g|l|t|x CABFILE [FILENAME...]\n"
+      "\t%s [-c COMPONENT] [-d DIRECTORY] [-D LEVEL] [-g GROUP] [-h] [-i VERSION] [-e ENCODING] [-j] [-L] [-O] [-r] [-R] [-t] [-V] c|g|l|t|x CABFILE [FILENAME...]\n"
       "\n"
       "Options:\n"
       "\t-c COMPONENT  Only list/extract this component\n"
@@ -211,6 +213,7 @@ static void show_usage(const char* name)
       "\t-O            Use old compression\n"
       "\t-r            Save raw data (do not decompress)\n"
       "\t-R            Don't do any conversion to file and directory names when extracting\n"
+      "\t-t            Set the modification date/time from the metadata when extracting\n"
       "\t-V --version  Print copyright and version information\n"
       "\n"
       "Commands:\n"
@@ -243,7 +246,7 @@ static bool handle_parameters(
        { NULL, 0, NULL, 0 }
     };
 
-    while ((c = getopt_long(argc, argv, "c:d:D:g:hi:e:jLOrRV", long_options, NULL)) != -1)
+    while ((c = getopt_long(argc, argv, "c:d:D:g:hi:e:jLOrRtV", long_options, NULL)) != -1)
     {
     switch (c)
     {
@@ -297,6 +300,10 @@ static bool handle_parameters(
         format = FORMAT_RAW;
         break;
 
+      case 't':
+        set_timestamp = true;
+        break;
+
       case 'V':
         printf("Unshield version " VERSION ". MIT License. (C) 2003-2023 David Eriksson.\n");
         exit(0);
@@ -540,6 +547,18 @@ static bool extract_file(Unshield* unshield, const char* prefix, int index)
       break;
   }
 
+  if (success && set_timestamp)
+  {
+    /* XXX: Use file function wrappers? */
+    struct utimbuf utim;
+    struct stat info;
+
+    stat(filename, &info);
+    utim.actime = info.st_atim.tv_sec;
+    utim.modtime = unshield_file_timestamp(unshield, index);
+    utime(filename, &utim);
+  }
+
 exit:
   if (!success)
   {