Changes in uspace/app/bdsh/cmds/modules/mkfile/mkfile.c [36ab7c7:f9d8c3a] in mainline

File:

• uspace/app/bdsh/cmds/modules/mkfile/mkfile.c (modified) (6 diffs)

uspace/app/bdsh/cmds/modules/mkfile/mkfile.c

@@ -54 +54 @@
 static struct option const long_options[] = {
         {"size", required_argument, 0, 's'},
+        {"sparse", no_argument, 0, 'p'},
         {"help", no_argument, 0, 'h'},
         {0, 0, 0, 0}
@@ -69 +70 @@
                 "  -h, --help       A short option summary\n"
                 "  -s, --size sz    Size of the file\n"
+                "  -p, --sparse     Create a sparse file\n"
                 "\n"
                 "Size is a number followed by 'k', 'm' or 'g' for kB, MB, GB.\n"
@@ -115 +117 @@
         ssize_t file_size;
         ssize_t total_written;
-        ssize_t to_write, rc;
+        ssize_t to_write, rc, rc2 = 0;
         char *file_name;
         void *buffer;
+        bool create_sparse = false;
 
         file_size = 0;
@@ -124 +127 @@
 
         for (c = 0, optind = 0, opt_ind = 0; c != -1;) {
-                c = getopt_long(argc, argv, "s:h", long_options, &opt_ind);
+                c = getopt_long(argc, argv, "ps:h", long_options, &opt_ind);
                 switch (c) {
                 case 'h':
                         help_cmd_mkfile(HELP_LONG);
                         return CMD_SUCCESS;
+                case 'p':
+                        create_sparse = true;
+                        break;
                 case 's':
                         file_size = read_size(optarg);
@@ -154 +160 @@
                 printf("%s: failed to create file %s.\n", cmdname, file_name);
                 return CMD_FAILURE;
+        }
+
+        if (create_sparse && file_size > 0) {
+                const char byte = 0x00;
+
+                if ((rc2 = lseek(fd, file_size - 1, SEEK_SET)) < 0)
+                        goto exit;
+
+                rc2 = write(fd, &byte, sizeof(char));
+                goto exit;
         }
 
@@ -174 +190 @@
         }
 
+        free(buffer);
+exit:
         rc = close(fd);
-        if (rc != 0) {
+
+        if (rc != 0 || rc2 < 0) {
                 printf("%s: Error writing file (%zd).\n", cmdname, rc);
                 return CMD_FAILURE;
         }
-
-        free(buffer);
 
         return CMD_SUCCESS;