#include "git-compat-util.h"

#include "abspath.h"

#include "strbuf.h"

/*

* Do not use this for inspecting *tracked* content. When path is a

* symlink to a directory, we do not want to say it is a directory when

* dealing with tracked content in the working tree.

*/

int is_directory(const char *path)

{

struct stat st;

return (!stat(path, &st) && S_ISDIR(st.st_mode));

}

/* removes the last path component from 'path' except if 'path' is root */

static void strip_last_component(struct strbuf *path)

{

size_t offset = offset_1st_component(path->buf);

size_t len = path->len;

/* Find start of the last component */

while (offset < len && !is_dir_sep(path->buf[len - 1]))

len--;

/* Skip sequences of multiple path-separators */

while (offset < len && is_dir_sep(path->buf[len - 1]))

len--;

strbuf_setlen(path, len);

}

/* get (and remove) the next component in 'remaining' and place it in 'next' */

static void get_next_component(struct strbuf *next, struct strbuf *remaining)

{

char *start = NULL;

char *end = NULL;

strbuf_reset(next);

/* look for the next component */

/* Skip sequences of multiple path-separators */

for (start = remaining->buf; is_dir_sep(*start); start++)

; /* nothing */

/* Find end of the path component */

for (end = start; *end && !is_dir_sep(*end); end++)

; /* nothing */

strbuf_add(next, start, end - start);

/* remove the component from 'remaining' */

strbuf_remove(remaining, 0, end - remaining->buf);

}

/* copies root part from remaining to resolved, canonicalizing it on the way */

static void get_root_part(struct strbuf *resolved, struct strbuf *remaining)

{

int offset = offset_1st_component(remaining->buf);

strbuf_reset(resolved);

strbuf_add(resolved, remaining->buf, offset);

#ifdef GIT_WINDOWS_NATIVE

convert_slashes(resolved->buf);

#endif

strbuf_remove(remaining, 0, offset);

}

/* We allow "recursive" symbolic links. Only within reason, though. */

#ifndef MAXSYMLINKS

#define MAXSYMLINKS 32

#endif

/*

* If set, any number of trailing components may be missing; otherwise, only one

* may be.

*/

#define REALPATH_MANY_MISSING (1 << 0)

/* Should we die if there's an error? */

#define REALPATH_DIE_ON_ERROR (1 << 1)

static char *strbuf_realpath_1(struct strbuf *resolved, const char *path,

int flags)

{

struct strbuf remaining = STRBUF_INIT;

struct strbuf next = STRBUF_INIT;

struct strbuf symlink = STRBUF_INIT;

char *retval = NULL;

int num_symlinks = 0;

struct stat st;

if (!*path) {

if (flags & REALPATH_DIE_ON_ERROR)

die("The empty string is not a valid path");

else

goto error_out;

}

strbuf_addstr(&remaining, path);

get_root_part(resolved, &remaining);

if (!resolved->len) {

/* relative path; can use CWD as the initial resolved path */

if (strbuf_getcwd(resolved)) {

if (flags & REALPATH_DIE_ON_ERROR)

die_errno("unable to get current working directory");

else

goto error_out;

}

}

/* Iterate over the remaining path components */

while (remaining.len > 0) {

get_next_component(&next, &remaining);

if (next.len == 0) {

continue; /* empty component */

} else if (next.len == 1 && !strcmp(next.buf, ".")) {

continue; /* '.' component */

} else if (next.len == 2 && !strcmp(next.buf, "..")) {

/* '..' component; strip the last path component */

strip_last_component(resolved);

continue;

}

/* append the next component and resolve resultant path */

if (!is_dir_sep(resolved->buf[resolved->len - 1]))

strbuf_addch(resolved, '/');

strbuf_addbuf(resolved, &next);

if (lstat(resolved->buf, &st)) {

/* error out unless this was the last component */

if (errno != ENOENT ||

(!(flags & REALPATH_MANY_MISSING) && remaining.len)) {

if (flags & REALPATH_DIE_ON_ERROR)

die_errno("Invalid path '%s'",

resolved->buf);

else

goto error_out;

}

} else if (S_ISLNK(st.st_mode)) {

ssize_t len;

strbuf_reset(&symlink);

if (num_symlinks++ > MAXSYMLINKS) {

errno = ELOOP;

if (flags & REALPATH_DIE_ON_ERROR)

die("More than %d nested symlinks "

"on path '%s'", MAXSYMLINKS, path);

else

goto error_out;

}

len = strbuf_readlink(&symlink, resolved->buf,

st.st_size);

if (len < 0) {

if (flags & REALPATH_DIE_ON_ERROR)

die_errno("Invalid symlink '%s'",

resolved->buf);

else

goto error_out;

}

if (is_absolute_path(symlink.buf)) {

/* absolute symlink; set resolved to root */

get_root_part(resolved, &symlink);

} else {

/*

* relative symlink

* strip off the last component since it will

* be replaced with the contents of the symlink

*/

strip_last_component(resolved);

}

/*

* if there are still remaining components to resolve

* then append them to symlink

*/

if (remaining.len) {

strbuf_addch(&symlink, '/');

strbuf_addbuf(&symlink, &remaining);

}

/*

* use the symlink as the remaining components that

* need to be resolved

*/

strbuf_swap(&symlink, &remaining);

}

}

retval = resolved->buf;

error_out:

strbuf_release(&remaining);

strbuf_release(&next);

strbuf_release(&symlink);

if (!retval)

strbuf_reset(resolved);

return retval;

}

/*

* Return the real path (i.e., absolute path, with symlinks resolved

* and extra slashes removed) equivalent to the specified path. (If

* you want an absolute path but don't mind links, use

* absolute_path().) Places the resolved realpath in the provided strbuf.

*

* The directory part of path (i.e., everything up to the last

* dir_sep) must denote a valid, existing directory, but the last

* component need not exist. If die_on_error is set, then die with an

* informative error message if there is a problem. Otherwise, return

* NULL on errors (without generating any output).

*/

char *strbuf_realpath(struct strbuf *resolved, const char *path,

int die_on_error)

{

return strbuf_realpath_1(resolved, path,

die_on_error ? REALPATH_DIE_ON_ERROR : 0);

}

/*

* Just like strbuf_realpath, but allows an arbitrary number of path

* components to be missing.

*/

char *strbuf_realpath_forgiving(struct strbuf *resolved, const char *path,

int die_on_error)

{

return strbuf_realpath_1(resolved, path,

((die_on_error ? REALPATH_DIE_ON_ERROR : 0) |

REALPATH_MANY_MISSING));

}

char *real_pathdup(const char *path, int die_on_error)

{

struct strbuf realpath = STRBUF_INIT;

char *retval = NULL;

if (strbuf_realpath(&realpath, path, die_on_error))

retval = strbuf_detach(&realpath, NULL);

strbuf_release(&realpath);

return retval;

}

/*

* Use this to get an absolute path from a relative one. If you want

* to resolve links, you should use strbuf_realpath.

*/

const char *absolute_path(const char *path)

{

static struct strbuf sb = STRBUF_INIT;

strbuf_reset(&sb);

strbuf_add_absolute_path(&sb, path);

return sb.buf;

}

char *absolute_pathdup(const char *path)

{

struct strbuf sb = STRBUF_INIT;

strbuf_add_absolute_path(&sb, path);

return strbuf_detach(&sb, NULL);

}

char *prefix_filename(const char *pfx, const char *arg)

{

struct strbuf path = STRBUF_INIT;

size_t pfx_len = pfx ? strlen(pfx) : 0;

if (!pfx_len)

; /* nothing to prefix */

else if (is_absolute_path(arg))

pfx_len = 0;

else

strbuf_add(&path, pfx, pfx_len);

strbuf_addstr(&path, arg);

#ifdef GIT_WINDOWS_NATIVE

convert_slashes(path.buf + pfx_len);

#endif

return strbuf_detach(&path, NULL);

}

char *prefix_filename_except_for_dash(const char *pfx, const char *arg)

{

if (!strcmp(arg, "-"))

return xstrdup(arg);

return prefix_filename(pfx, arg);

}

void strbuf_add_absolute_path(struct strbuf *sb, const char *path)

{

if (!*path)

die("The empty string is not a valid path");

if (!is_absolute_path(path)) {

struct stat cwd_stat, pwd_stat;

size_t orig_len = sb->len;

char *cwd = xgetcwd();

char *pwd = getenv("PWD");

if (pwd && strcmp(pwd, cwd) &&

!stat(cwd, &cwd_stat) &&

(cwd_stat.st_dev || cwd_stat.st_ino) &&

!stat(pwd, &pwd_stat) &&

pwd_stat.st_dev == cwd_stat.st_dev &&

pwd_stat.st_ino == cwd_stat.st_ino)

strbuf_addstr(sb, pwd);

else

strbuf_addstr(sb, cwd);

if (sb->len > orig_len && !is_dir_sep(sb->buf[sb->len - 1]))

strbuf_addch(sb, '/');

free(cwd);

}

strbuf_addstr(sb, path);

}

void strbuf_add_real_path(struct strbuf *sb, const char *path)

{

if (sb->len) {

struct strbuf resolved = STRBUF_INIT;

strbuf_realpath(&resolved, path, 1);

strbuf_addbuf(sb, &resolved);

strbuf_release(&resolved);

} else

strbuf_realpath(sb, path, 1);

}