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                 fclose(f);
  41                 return NULL;
  42         }
  43
  44         fclose(f);
  45
  46         /* make sure the string is \0 terminated */
  47         buf[bufsz - 1] = '\0';
  48
  49         /* remove trailing whitespace */
  50         i = strlen(buf) - 1;
  51         while (i > 0 && buf[i] <= ' ')
  52                 buf[i--] = '\0';
  53
  54         return buf;
  55 }
  56
  57 int block_file_identify(FILE *f, uint64_t offset)
  58 {
  59         uint32_t magic = 0;
  60         size_t n;
  61
  62         fseeko(f, offset, SEEK_SET);
  63         n = fread(&magic, sizeof(magic), 1, f);
  64         if (magic == cpu_to_le32(0x88b1f)) {
  65                 return FS_TARGZ;
  66         }
  67
  68         fseeko(f, offset + 0x400, SEEK_SET);
  69         n = fread(&magic, sizeof(magic), 1, f);
  70         if (n != 1)
  71                 return -1;
  72
  73         if (magic == cpu_to_le32(0xF2F52010))
  74                 return FS_F2FS;
  75
  76         magic = 0;
  77         fseeko(f, offset + 0x438, SEEK_SET);
  78         n = fread(&magic, sizeof(magic), 1, f);
  79         if (n != 1)
  80                 return -1;
  81
  82         if ((le32_to_cpu(magic) & 0xffff) == 0xef53)
  83                 return FS_EXT4;
  84
  85         return FS_NONE;
  86 }
  87
  88 static bool use_f2fs(struct volume *v, uint64_t offset, const char *bdev)
  89 {
  90         uint64_t size = 0;
  91         bool ret = false;
  92         int fd;
  93
  94         fd = open(bdev, O_RDONLY);
  95         if (fd < 0)
  96                 return false;
  97
  98         if (ioctl(fd, BLKGETSIZE64, &size) == 0)
  99                 ret = size - offset > F2FS_MINSIZE;
 100
 101         close(fd);
 102
 103         return ret;
 104 }
 105
 106 int block_volume_format(struct volume *v, uint64_t offset, const char *bdev)
 107 {
 108         int ret = 0;
 109         char str[128];
 110
 111         switch (volume_identify(v)) {
 112         case FS_TARGZ:
 113                 snprintf(str, sizeof(str), "gzip -cd %s > /tmp/sysupgrade.tar", v->blk);
 114                 system(str);
 115                 /* fall-through */
 116         case FS_NONE:
 117                 ULOG_INFO("overlay filesystem in %s has not been formatted yet\n", v->blk);
 118                 if (use_f2fs(v, offset, bdev))
 119                         snprintf(str, sizeof(str), "mkfs.f2fs -q -l rootfs_data %s", v->blk);
 120                 else
 121                         snprintf(str, sizeof(str), "mkfs.ext4 -q -L rootfs_data %s", v->blk);
 122
 123                 ret = system(str);
 124                 break;
 125         default:
 126                 break;
 127         }
 128
 129         return ret;
 130 }