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         if (fseeko(f, offset, SEEK_SET) < 0)
  63                 return -1;
  64
  65         n = fread(&magic, sizeof(magic), 1, f);
  66         if (magic == cpu_to_le32(0x88b1f)) {
  67                 return FS_TARGZ;
  68         }
  69
  70         if (fseeko(f, offset + 0x400, SEEK_SET) < 0)
  71                 return -1;
  72
  73         n = fread(&magic, sizeof(magic), 1, f);
  74         if (n != 1)
  75                 return -1;
  76
  77         if (magic == cpu_to_le32(0xF2F52010))
  78                 return FS_F2FS;
  79
  80         magic = 0;
  81         if (fseeko(f, offset + 0x438, SEEK_SET) < 0)
  82                 return -1;
  83
  84         n = fread(&magic, sizeof(magic), 1, f);
  85         if (n != 1)
  86                 return -1;
  87
  88         if ((le32_to_cpu(magic) & 0xffff) == 0xef53)
  89                 return FS_EXT4;
  90
  91         return FS_NONE;
  92 }
  93
  94 static bool use_f2fs(struct volume *v, uint64_t offset, const char *bdev)
  95 {
  96         uint64_t size = 0;
  97         bool ret = false;
  98         int fd;
  99
 100         fd = open(bdev, O_RDONLY);
 101         if (fd < 0)
 102                 return false;
 103
 104         if (ioctl(fd, BLKGETSIZE64, &size) == 0)
 105                 ret = size - offset > F2FS_MINSIZE;
 106
 107         close(fd);
 108
 109         return ret;
 110 }
 111
 112 int block_volume_format(struct volume *v, uint64_t offset, const char *bdev)
 113 {
 114         int ret = 0;
 115         char str[128];
 116
 117         switch (volume_identify(v)) {
 118         case FS_TARGZ:
 119                 snprintf(str, sizeof(str), "gzip -cd %s > /tmp/sysupgrade.tar", v->blk);
 120                 system(str);
 121                 /* fall-through */
 122         case FS_NONE:
 123                 ULOG_INFO("overlay filesystem in %s has not been formatted yet\n", v->blk);
 124                 if (use_f2fs(v, offset, bdev))
 125                         snprintf(str, sizeof(str), "mkfs.f2fs -q -l rootfs_data %s", v->blk);
 126                 else
 127                         snprintf(str, sizeof(str), "mkfs.ext4 -q -L rootfs_data %s", v->blk);
 128
 129                 ret = system(str);
 130                 break;
 131         default:
 132                 break;
 133         }
 134
 135         return ret;
 136 }