fs.c
1.95 KB
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/* TODO merge/factor into tools/lib/lk/debugfs.c */
#include "util.h"
#include "util/fs.h"
static const char * const sysfs__fs_known_mountpoints[] = {
"/sys",
0,
};
static const char * const procfs__known_mountpoints[] = {
"/proc",
0,
};
struct fs {
const char *name;
const char * const *mounts;
char path[PATH_MAX + 1];
bool found;
long magic;
};
enum {
FS__SYSFS = 0,
FS__PROCFS = 1,
};
static struct fs fs__entries[] = {
[FS__SYSFS] = {
.name = "sysfs",
.mounts = sysfs__fs_known_mountpoints,
.magic = SYSFS_MAGIC,
},
[FS__PROCFS] = {
.name = "proc",
.mounts = procfs__known_mountpoints,
.magic = PROC_SUPER_MAGIC,
},
};
static bool fs__read_mounts(struct fs *fs)
{
bool found = false;
char type[100];
FILE *fp;
fp = fopen("/proc/mounts", "r");
if (fp == NULL)
return NULL;
while (!found &&
fscanf(fp, "%*s %" STR(PATH_MAX) "s %99s %*s %*d %*d\n",
fs->path, type) == 2) {
if (strcmp(type, fs->name) == 0)
found = true;
}
fclose(fp);
return fs->found = found;
}
static int fs__valid_mount(const char *fs, long magic)
{
struct statfs st_fs;
if (statfs(fs, &st_fs) < 0)
return -ENOENT;
else if (st_fs.f_type != magic)
return -ENOENT;
return 0;
}
static bool fs__check_mounts(struct fs *fs)
{
const char * const *ptr;
ptr = fs->mounts;
while (*ptr) {
if (fs__valid_mount(*ptr, fs->magic) == 0) {
fs->found = true;
strcpy(fs->path, *ptr);
return true;
}
ptr++;
}
return false;
}
static const char *fs__get_mountpoint(struct fs *fs)
{
if (fs__check_mounts(fs))
return fs->path;
return fs__read_mounts(fs) ? fs->path : NULL;
}
static const char *fs__mountpoint(int idx)
{
struct fs *fs = &fs__entries[idx];
if (fs->found)
return (const char *)fs->path;
return fs__get_mountpoint(fs);
}
#define FS__MOUNTPOINT(name, idx) \
const char *name##__mountpoint(void) \
{ \
return fs__mountpoint(idx); \
}
FS__MOUNTPOINT(sysfs, FS__SYSFS);
FS__MOUNTPOINT(procfs, FS__PROCFS);