libfstools/common.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2
   3 #include "common.h"
   4 #define BUFLEN 128
   5
   6 int
   7 read_uint_from_file(char *dirname, char *filename, unsigned int *i)
   8 {
   9         FILE *f;
  10         char fname[BUFLEN];
  11         int ret = -1;
  12
  13         snprintf(fname, sizeof(fname), "%s/%s", dirname, filename);
  14
  15         f = fopen(fname, "r");
  16         if (!f)
  17                 return ret;
  18
  19         if (fscanf(f, "%u", i) == 1)
  20                 ret = 0;
  21
  22         fclose(f);
  23         return ret;
  24 }
  25
  26 char
  27 *read_string_from_file(const char *dirname, const char *filename, char *buf, size_t bufsz)
  28 {
  29         FILE *f;
  30         char fname[BUFLEN];
  31         int i;
  32
  33         snprintf(fname, sizeof(fname), "%s/%s", dirname, filename);
  34
  35         f = fopen(fname, "r");
  36         if (!f)
  37                 return NULL;
  38
  39         if (fgets(buf, bufsz, f) == NULL)
  40                 return NULL;
  41
  42         fclose(f);
  43
  44         /* make sure the string is \0 terminated */
  45         buf[bufsz - 1] = '\0';
  46
  47         /* remove trailing whitespace */
  48         i = strlen(buf) - 1;
  49         while (i > 0 && buf[i] <= ' ')
  50                 buf[i--] = '\0';
  51
  52         return buf;
  53 }
  54
  55 int block_file_identify(FILE *f, uint64_t offset)
  56 {
  57         uint32_t magic = 0;
  58         size_t n;
  59
  60         fseeko(f, offset, SEEK_SET);
  61         n = fread(&magic, sizeof(magic), 1, f);
  62         if (magic == cpu_to_le32(0x88b1f)) {
  63                 return FS_TARGZ;
  64         }
  65
  66         fseeko(f, offset + 0x400, SEEK_SET);
  67         n = fread(&magic, sizeof(magic), 1, f);
  68         if (n != 1)
  69                 return -1;
  70
  71         if (magic == cpu_to_le32(0xF2F52010))
  72                 return FS_F2FS;
  73
  74         magic = 0;
  75         fseeko(f, offset + 0x438, SEEK_SET);
  76         n = fread(&magic, sizeof(magic), 1, f);
  77         if (n != 1)
  78                 return -1;
  79
  80         if ((le32_to_cpu(magic) & 0xffff) == 0xef53)
  81                 return FS_EXT4;
  82
  83         return FS_NONE;
  84 }
  85
  86 static bool use_f2fs(struct volume *v, uint64_t offset, const char *bdev)
  87 {
  88         uint64_t size = 0;
  89         bool ret = false;
  90         int fd;
  91
  92         fd = open(bdev, O_RDONLY);
  93         if (ioctl(fd, BLKGETSIZE64, &size) == 0)
  94                 ret = size - offset > F2FS_MINSIZE;
  95         close(fd);
  96
  97         return ret;
  98 }
  99
 100 int block_volume_format(struct volume *v, uint64_t offset, const char *bdev)
 101 {
 102         int ret = 0;
 103         char str[128];
 104
 105         switch (volume_identify(v)) {
 106         case FS_TARGZ:
 107                 snprintf(str, sizeof(str), "gzip -cd %s > /tmp/sysupgrade.tar", v->blk);
 108                 system(str);
 109                 /* fall-through */
 110         case FS_NONE:
 111                 ULOG_INFO("overlay filesystem in %s has not been formatted yet\n", v->blk);
 112                 if (use_f2fs(v, offset, bdev))
 113                         snprintf(str, sizeof(str), "mkfs.f2fs -q -l rootfs_data %s", v->blk);
 114                 else
 115                         snprintf(str, sizeof(str), "mkfs.ext4 -q -L rootfs_data %s", v->blk);
 116
 117                 ret = system(str);
 118                 break;
 119         default:
 120                 break;
 121         }
 122
 123         return ret;
 124 }