AP_Filesystem: added set_mtime() call

libraries/AP_Filesystem/AP_Filesystem.h

@@ -60,6 +60,9 @@ public:
 
     // return total disk space in bytes, -1 on error
     int64_t disk_space(const char *path);
+
+    // set modification time on a file
+    bool set_mtime(const char *filename, const time_t mtime_sec);
 };
 
 namespace AP {

libraries/AP_Filesystem/AP_Filesystem_FATFS.cpp

@@ -779,6 +779,39 @@ int64_t AP_Filesystem::disk_space(const char *path)
     return (int64_t)(tot_sect)*512;
 }
 
+/*
+  convert unix time_t to FATFS timestamp
+ */
+static void unix_time_to_fat(time_t epoch, uint16_t &date, uint16_t &time)
+{
+    struct tm *t = gmtime((time_t *)&epoch);
+
+    /* Pack date and time into a uint32_t variable */
+    date = ((uint16_t)(t->tm_year - 80) << 9)
+        | (((uint16_t)t->tm_mon+1) << 5)
+        | (((uint16_t)t->tm_mday));
+
+    time = ((uint16_t)t->tm_hour << 11)
+        | ((uint16_t)t->tm_min << 5)
+        | ((uint16_t)t->tm_sec >> 1);
+}
+
+/*
+  set mtime on a file
+ */
+bool AP_Filesystem::set_mtime(const char *filename, const time_t mtime_sec)
+{
+    FILINFO fno;
+    uint16_t fdate, ftime;
+
+    unix_time_to_fat(mtime_sec, fdate, ftime);
+
+    fno.fdate = fdate;
+    fno.ftime = ftime;
+
+    return f_utime(filename, (FILINFO *)&fno) == FR_OK;
+}
+
 /*
   convert POSIX errno to text with user message.
 */

libraries/AP_Filesystem/AP_Filesystem_posix.cpp

@@ -21,6 +21,7 @@
 #if CONFIG_HAL_BOARD == HAL_BOARD_SITL || CONFIG_HAL_BOARD == HAL_BOARD_LINUX
 
 #include <sys/vfs.h>
+#include <utime.h>
 
 extern const AP_HAL::HAL& hal;
 
@@ -106,5 +107,17 @@ int64_t AP_Filesystem::disk_space(const char *path)
 }
 
 
+/*
+  set mtime on a file
+ */
+bool AP_Filesystem::set_mtime(const char *filename, const time_t mtime_sec)
+{
+    struct utimbuf times {};
+    times.actime = mtime_sec;
+    times.modtime = mtime_sec;
+
+    return utime(filename, &times) == 0;
+}
+
 #endif // CONFIG_HAL_BOARD