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#include <stdio.h>
#include <stdbool.h>
#include <string.h>
#include <dprintf.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);
}
static size_t copy_string(char *buf, size_t ix, size_t bufsize, const char *src)
{
char c;
while ((c = *src++)) {
if (ix+1 < bufsize)
buf[ix] = c;
ix++;
}
if (ix < bufsize)
buf[ix] = '\0';
return ix;
}
static size_t generic_inode_to_path(struct inode *inode, char *dst, size_t bufsize)
{
size_t s = 0;
dprintf("inode %p name %s\n", inode, inode->name);
if (inode->parent) {
if (!inode->name) /* Only the root should have no name */
return -1;
s = generic_inode_to_path(inode->parent, dst, bufsize);
if (s == (size_t)-1)
return s; /* Error! */
s = copy_string(dst, s, bufsize, "/");
s = copy_string(dst, s, bufsize, inode->name);
}
return s;
}
size_t realpath(char *dst, const char *src, size_t bufsize)
{
int rv;
struct file *file;
size_t s;
dprintf("realpath: input: %s\n", src);
if (this_fs->fs_ops->realpath) {
s = this_fs->fs_ops->realpath(this_fs, dst, src, bufsize);
} else {
rv = searchdir(src);
if (rv < 0) {
dprintf("realpath: searchpath failure\n");
return -1;
}
file = handle_to_file(rv);
s = generic_inode_to_path(file->inode, dst, bufsize);
if (s == 0)
s = copy_string(dst, 0, bufsize, "/");
_close_file(file);
}
dprintf("realpath: output: %s\n", dst);
return s;
}
int chdir(const char *src)
{
int rv;
struct file *file;
char cwd_buf[CURRENTDIR_MAX];
size_t s;
dprintf("chdir: from %s (inode %p) add %s\n",
this_fs->cwd_name, this_fs->cwd, src);
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 */
s = generic_inode_to_path(this_fs->cwd, cwd_buf, CURRENTDIR_MAX-1);
/* Make sure the cwd_name ends in a slash, it's supposed to be a prefix */
if (s < 1 || cwd_buf[s-1] != '/')
cwd_buf[s++] = '/';
if (s >= CURRENTDIR_MAX)
s = CURRENTDIR_MAX - 1;
cwd_buf[s++] = '\0';
memcpy(this_fs->cwd_name, cwd_buf, s);
dprintf("chdir: final %s (inode %p)\n",
this_fs->cwd_name, this_fs->cwd);
return 0;
}
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