Decode and apply MSDOS file timestamps

diff --git a/installshield_main.c b/installshield_main.c
index 4b1fa8e..bb6654a 100644 (file)
--- a/installshield_main.c
+++ b/installshield_main.c
@@ -15,6 +15,8 @@
 #include <unistd.h>
 #include <errno.h>
 #include <string.h>
+#include <time.h>
+#include <utime.h>
 
 #include "implode.h"
 #include "installshield_z.h"
@@ -32,6 +34,20 @@ usage(const char *name)
        );
 }
 
+time_t msdos2unixtime(uint16_t time, uint16_t date)
+{
+       if (debug) printf("Date: %04x Time %04x\n", date, time);
+       struct tm dt;
+       dt.tm_year              =((date & 0xFE00) >>  9) + 80;
+       dt.tm_mon               = (date & 0x01E0) >>  5;
+       dt.tm_mday              = (date & 0x001F) >>  0;
+       dt.tm_hour              = (time & 0xF800) >> 11;
+       dt.tm_min               = (time & 0x07E0) >>  5;
+       dt.tm_sec               = (time & 0x001F) >>  0;
+
+       return mktime(&dt);
+}
+
 int
 headers_decode(int z_fd)
 {
@@ -81,7 +97,9 @@ headers_decode(int z_fd)
                                printf("File entries: %d ( %08x bytes @ 0x%08x)\n", header->files_entries, header->files_bytes, header->files_offset);
 
                                for (int i = 0; i < header->files_entries; ++i) {
-                                       printf(" Entry %4d uses %06x bytes @ %08x. file-size %08x (payload %08x @ %08x)", i, q->entry_bytes, header->files_offset +(uint32_t)((void *)q - (void *)fileent), q->file_bytes, q->payload_bytes, q->payload_offset);
+                                       time_t timestamp = msdos2unixtime(q->timestamp, q->datestamp);
+                                       char *datetime = ctime(&timestamp);
+                                       printf(" Entry %4d uses %06x bytes @ %08x. Date %s File-size %08x (payload %08x @ %08x)", i, q->entry_bytes, header->files_offset +(uint32_t)((void *)q - (void *)fileent), datetime, q->file_bytes, q->payload_bytes, q->payload_offset);
 
                                        if (debug) {
                                                printf(" next @ %08x", q->payload_offset + q->payload_bytes);
@@ -146,7 +164,12 @@ headers_decode(int z_fd)
                                                unsigned int z_filename_len = strlen(q->name) + 4;
                                                char z_filename[z_filename_len];
                                                strncpy(z_filename, q->name, z_filename_len);
-                                               strncat(z_filename, ".z", 2);
+                                               strncat(z_filename, ".z", 3);
+
+                                               char filepath[strlen(dir_name) + z_filename_len];
+                                               strncpy(filepath, dir_name, strlen(dir_name) + 1);
+                                               strncat(filepath, "/", 2);
+                                               strncat(filepath, z_filename, z_filename_len);
 
                                                if (debug)
                                                        printf(" Creating payload file '%s/%s'\n", dir_name,  z_filename);
@@ -154,6 +177,9 @@ headers_decode(int z_fd)
                                                if ((offset = lseek(z_fd, q->payload_offset, SEEK_SET)) == q->payload_offset) {
                                                        void *buffer;
                                                        if ((buffer = calloc(q->payload_bytes, 1)) != 0) {
+                                                               struct utimbuf filetime;
+                                                               filetime.actime  = timestamp;
+                                                               filetime.modtime = timestamp;
                                                                int pay_fd;
                                                                if ((pay_fd = openat(dir_fd, z_filename, O_WRONLY | O_CREAT | O_TRUNC, 0644))) {
                                                                        ssize_t z_qty, pay_qty;
@@ -170,6 +196,10 @@ headers_decode(int z_fd)
                                                                        } else
                                                                                fprintf(stderr, "Error: whilst reading payload expected %d bytes but read %ld\n", q->payload_bytes, z_qty);
                                                                        close(pay_fd);
+                                                                       if(utime(filepath, &filetime) == -1) {
+                                                                               fprintf(stderr, "Error: unable to set timestamp on '%s' (%d) ", filepath, errno);
+                                                                               perror(NULL);
+                                                                       }
                                                                }
                                                                if (q->payload_bytes >= 4) {
                                                                        uint8_t comp_type = *(uint8_t *)buffer;
@@ -190,6 +220,11 @@ headers_decode(int z_fd)
                                                                                                        if ((decomp_qty = write(decomp_fd, buffer_decomp, q->file_bytes)) != q->file_bytes)
                                                                                                                fprintf(stderr, "Error: whilst writing decompressed data expected %d bytes but wrote %ld\n", q->file_bytes, decomp_qty);
                                                                                                        close(decomp_fd);
+                                                                                                       filepath[strlen(filepath) - 2] = 0;
+                                                                                                       if(utime(filepath, &filetime) == -1) {
+                                                                                                               fprintf(stderr, "Error: unable to set timestamp on '%s' (%d) ", filepath, errno);
+                                                                                                               perror(NULL);
+                                                                                                       }
                                                                                                }
                                                                                        } else {
                                                                                                fprintf(stderr, "Error: failed to decompress '%s', payload: %d decompressed: %d\n", q->name, q->payload_bytes, decomp_bytes);

diff --git a/installshield_z.h b/installshield_z.h
index d55277c..e49b7a4 100644 (file)
--- a/installshield_z.h
+++ b/installshield_z.h
@@ -54,7 +54,8 @@ struct __attribute__((packed)) fileent_prefix {
        uint32_t                        file_bytes;
        uint32_t                        payload_bytes;
        uint32_t                        payload_offset;
-       uint32_t                        __crc32;
+       uint16_t                        datestamp;
+       uint16_t                        timestamp;
        uint32_t                        __unknown13;
        uint16_t                        entry_bytes;
        uint32_t                        __unknown01;