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#include <stdio.h>
#include <stdbool.h>
#include <string.h>
#include "fs.h"
#include "cache.h"
/*
* Convert a relative pathname to an absolute pathname
* In the future this might also resolve symlinks...
*/
void pm_realpath(com32sys_t *regs)
{
const char *src = MK_PTR(regs->ds, regs->esi.w[0]);
char *dst = MK_PTR(regs->es, regs->edi.w[0]);
realpath(dst, src, FILENAME_MAX);
}
#define EMIT(x) \
do { \
if (++n < bufsize) \
*q++ = (x); \
} while (0)
static size_t join_paths(char *dst, size_t bufsize,
const char *s1, const char *s2)
{
const char *list[2];
int i;
char c;
const char *p;
char *q = dst;
size_t n = 0;
bool slash = false;
list[0] = s1;
list[1] = s2;
for (i = 0; i < 2; i++) {
p = list[i];
while ((c = *p++)) {
if (c == '/') {
if (!slash)
EMIT(c);
slash = true;
} else {
EMIT(c);
slash = false;
}
}
}
if (bufsize)
*q = '\0';
return n;
}
size_t realpath(char *dst, const char *src, size_t bufsize)
{
if (this_fs->fs_ops->realpath) {
return this_fs->fs_ops->realpath(this_fs, dst, src, bufsize);
} else {
/* Filesystems with "common" pathname resolution */
return join_paths(dst, bufsize,
src[0] == '/' ? "" : this_fs->cwd_name,
src);
}
}
int chdir(const char *src)
{
int rv;
struct file *file;
char cwd_buf[CURRENTDIR_MAX];
if (this_fs->fs_ops->chdir)
return this_fs->fs_ops->chdir(this_fs, src);
/* Otherwise it is a "conventional filesystem" */
rv = searchdir(src);
if (rv < 0)
return rv;
file = handle_to_file(rv);
if (file->inode->mode != DT_DIR) {
_close_file(file);
return -1;
}
put_inode(this_fs->cwd);
this_fs->cwd = get_inode(file->inode);
_close_file(file);
/* Save the current working directory */
realpath(cwd_buf, src, CURRENTDIR_MAX);
/* Make sure the cwd_name ends in a slash, it's supposed to be a prefix */
join_paths(this_fs->cwd_name, CURRENTDIR_MAX, cwd_buf, "/");
return 0;
}
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