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git/dir.c
Linus Torvalds 443e061a41 Avoid using 'lstat()' to figure out directories
If we have an up-to-date index entry for a file in that directory, we
can know that the directories leading up to that file must be
directories.  No need to do an lstat() on the directory.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2009-07-09 20:05:19 -07:00

933 lines
22 KiB
C

/*
* This handles recursive filename detection with exclude
* files, index knowledge etc..
*
* Copyright (C) Linus Torvalds, 2005-2006
* Junio Hamano, 2005-2006
*/
#include "cache.h"
#include "dir.h"
#include "refs.h"
struct path_simplify {
int len;
const char *path;
};
static int read_directory_recursive(struct dir_struct *dir, const char *path, int len,
int check_only, const struct path_simplify *simplify);
static int get_dtype(struct dirent *de, const char *path, int len);
static int common_prefix(const char **pathspec)
{
const char *path, *slash, *next;
int prefix;
if (!pathspec)
return 0;
path = *pathspec;
slash = strrchr(path, '/');
if (!slash)
return 0;
prefix = slash - path + 1;
while ((next = *++pathspec) != NULL) {
int len = strlen(next);
if (len >= prefix && !memcmp(path, next, prefix))
continue;
len = prefix - 1;
for (;;) {
if (!len)
return 0;
if (next[--len] != '/')
continue;
if (memcmp(path, next, len+1))
continue;
prefix = len + 1;
break;
}
}
return prefix;
}
int fill_directory(struct dir_struct *dir, const char **pathspec)
{
const char *path;
int len;
/*
* Calculate common prefix for the pathspec, and
* use that to optimize the directory walk
*/
len = common_prefix(pathspec);
path = "";
if (len)
path = xmemdupz(*pathspec, len);
/* Read the directory and prune it */
read_directory(dir, path, len, pathspec);
return len;
}
/*
* Does 'match' match the given name?
* A match is found if
*
* (1) the 'match' string is leading directory of 'name', or
* (2) the 'match' string is a wildcard and matches 'name', or
* (3) the 'match' string is exactly the same as 'name'.
*
* and the return value tells which case it was.
*
* It returns 0 when there is no match.
*/
static int match_one(const char *match, const char *name, int namelen)
{
int matchlen;
/* If the match was just the prefix, we matched */
if (!*match)
return MATCHED_RECURSIVELY;
for (;;) {
unsigned char c1 = *match;
unsigned char c2 = *name;
if (c1 == '\0' || is_glob_special(c1))
break;
if (c1 != c2)
return 0;
match++;
name++;
namelen--;
}
/*
* If we don't match the matchstring exactly,
* we need to match by fnmatch
*/
matchlen = strlen(match);
if (strncmp(match, name, matchlen))
return !fnmatch(match, name, 0) ? MATCHED_FNMATCH : 0;
if (namelen == matchlen)
return MATCHED_EXACTLY;
if (match[matchlen-1] == '/' || name[matchlen] == '/')
return MATCHED_RECURSIVELY;
return 0;
}
/*
* Given a name and a list of pathspecs, see if the name matches
* any of the pathspecs. The caller is also interested in seeing
* all pathspec matches some names it calls this function with
* (otherwise the user could have mistyped the unmatched pathspec),
* and a mark is left in seen[] array for pathspec element that
* actually matched anything.
*/
int match_pathspec(const char **pathspec, const char *name, int namelen,
int prefix, char *seen)
{
int i, retval = 0;
if (!pathspec)
return 1;
name += prefix;
namelen -= prefix;
for (i = 0; pathspec[i] != NULL; i++) {
int how;
const char *match = pathspec[i] + prefix;
if (seen && seen[i] == MATCHED_EXACTLY)
continue;
how = match_one(match, name, namelen);
if (how) {
if (retval < how)
retval = how;
if (seen && seen[i] < how)
seen[i] = how;
}
}
return retval;
}
static int no_wildcard(const char *string)
{
return string[strcspn(string, "*?[{\\")] == '\0';
}
void add_exclude(const char *string, const char *base,
int baselen, struct exclude_list *which)
{
struct exclude *x;
size_t len;
int to_exclude = 1;
int flags = 0;
if (*string == '!') {
to_exclude = 0;
string++;
}
len = strlen(string);
if (len && string[len - 1] == '/') {
char *s;
x = xmalloc(sizeof(*x) + len);
s = (char *)(x+1);
memcpy(s, string, len - 1);
s[len - 1] = '\0';
string = s;
x->pattern = s;
flags = EXC_FLAG_MUSTBEDIR;
} else {
x = xmalloc(sizeof(*x));
x->pattern = string;
}
x->to_exclude = to_exclude;
x->patternlen = strlen(string);
x->base = base;
x->baselen = baselen;
x->flags = flags;
if (!strchr(string, '/'))
x->flags |= EXC_FLAG_NODIR;
if (no_wildcard(string))
x->flags |= EXC_FLAG_NOWILDCARD;
if (*string == '*' && no_wildcard(string+1))
x->flags |= EXC_FLAG_ENDSWITH;
ALLOC_GROW(which->excludes, which->nr + 1, which->alloc);
which->excludes[which->nr++] = x;
}
static int add_excludes_from_file_1(const char *fname,
const char *base,
int baselen,
char **buf_p,
struct exclude_list *which)
{
struct stat st;
int fd, i;
size_t size;
char *buf, *entry;
fd = open(fname, O_RDONLY);
if (fd < 0 || fstat(fd, &st) < 0)
goto err;
size = xsize_t(st.st_size);
if (size == 0) {
close(fd);
return 0;
}
buf = xmalloc(size+1);
if (read_in_full(fd, buf, size) != size)
{
free(buf);
goto err;
}
close(fd);
if (buf_p)
*buf_p = buf;
buf[size++] = '\n';
entry = buf;
for (i = 0; i < size; i++) {
if (buf[i] == '\n') {
if (entry != buf + i && entry[0] != '#') {
buf[i - (i && buf[i-1] == '\r')] = 0;
add_exclude(entry, base, baselen, which);
}
entry = buf + i + 1;
}
}
return 0;
err:
if (0 <= fd)
close(fd);
return -1;
}
void add_excludes_from_file(struct dir_struct *dir, const char *fname)
{
if (add_excludes_from_file_1(fname, "", 0, NULL,
&dir->exclude_list[EXC_FILE]) < 0)
die("cannot use %s as an exclude file", fname);
}
static void prep_exclude(struct dir_struct *dir, const char *base, int baselen)
{
struct exclude_list *el;
struct exclude_stack *stk = NULL;
int current;
if ((!dir->exclude_per_dir) ||
(baselen + strlen(dir->exclude_per_dir) >= PATH_MAX))
return; /* too long a path -- ignore */
/* Pop the ones that are not the prefix of the path being checked. */
el = &dir->exclude_list[EXC_DIRS];
while ((stk = dir->exclude_stack) != NULL) {
if (stk->baselen <= baselen &&
!strncmp(dir->basebuf, base, stk->baselen))
break;
dir->exclude_stack = stk->prev;
while (stk->exclude_ix < el->nr)
free(el->excludes[--el->nr]);
free(stk->filebuf);
free(stk);
}
/* Read from the parent directories and push them down. */
current = stk ? stk->baselen : -1;
while (current < baselen) {
struct exclude_stack *stk = xcalloc(1, sizeof(*stk));
const char *cp;
if (current < 0) {
cp = base;
current = 0;
}
else {
cp = strchr(base + current + 1, '/');
if (!cp)
die("oops in prep_exclude");
cp++;
}
stk->prev = dir->exclude_stack;
stk->baselen = cp - base;
stk->exclude_ix = el->nr;
memcpy(dir->basebuf + current, base + current,
stk->baselen - current);
strcpy(dir->basebuf + stk->baselen, dir->exclude_per_dir);
add_excludes_from_file_1(dir->basebuf,
dir->basebuf, stk->baselen,
&stk->filebuf, el);
dir->exclude_stack = stk;
current = stk->baselen;
}
dir->basebuf[baselen] = '\0';
}
/* Scan the list and let the last match determine the fate.
* Return 1 for exclude, 0 for include and -1 for undecided.
*/
static int excluded_1(const char *pathname,
int pathlen, const char *basename, int *dtype,
struct exclude_list *el)
{
int i;
if (el->nr) {
for (i = el->nr - 1; 0 <= i; i--) {
struct exclude *x = el->excludes[i];
const char *exclude = x->pattern;
int to_exclude = x->to_exclude;
if (x->flags & EXC_FLAG_MUSTBEDIR) {
if (*dtype == DT_UNKNOWN)
*dtype = get_dtype(NULL, pathname, pathlen);
if (*dtype != DT_DIR)
continue;
}
if (x->flags & EXC_FLAG_NODIR) {
/* match basename */
if (x->flags & EXC_FLAG_NOWILDCARD) {
if (!strcmp(exclude, basename))
return to_exclude;
} else if (x->flags & EXC_FLAG_ENDSWITH) {
if (x->patternlen - 1 <= pathlen &&
!strcmp(exclude + 1, pathname + pathlen - x->patternlen + 1))
return to_exclude;
} else {
if (fnmatch(exclude, basename, 0) == 0)
return to_exclude;
}
}
else {
/* match with FNM_PATHNAME:
* exclude has base (baselen long) implicitly
* in front of it.
*/
int baselen = x->baselen;
if (*exclude == '/')
exclude++;
if (pathlen < baselen ||
(baselen && pathname[baselen-1] != '/') ||
strncmp(pathname, x->base, baselen))
continue;
if (x->flags & EXC_FLAG_NOWILDCARD) {
if (!strcmp(exclude, pathname + baselen))
return to_exclude;
} else {
if (fnmatch(exclude, pathname+baselen,
FNM_PATHNAME) == 0)
return to_exclude;
}
}
}
}
return -1; /* undecided */
}
int excluded(struct dir_struct *dir, const char *pathname, int *dtype_p)
{
int pathlen = strlen(pathname);
int st;
const char *basename = strrchr(pathname, '/');
basename = (basename) ? basename+1 : pathname;
prep_exclude(dir, pathname, basename-pathname);
for (st = EXC_CMDL; st <= EXC_FILE; st++) {
switch (excluded_1(pathname, pathlen, basename,
dtype_p, &dir->exclude_list[st])) {
case 0:
return 0;
case 1:
return 1;
}
}
return 0;
}
static struct dir_entry *dir_entry_new(const char *pathname, int len)
{
struct dir_entry *ent;
ent = xmalloc(sizeof(*ent) + len + 1);
ent->len = len;
memcpy(ent->name, pathname, len);
ent->name[len] = 0;
return ent;
}
static struct dir_entry *dir_add_name(struct dir_struct *dir, const char *pathname, int len)
{
if (cache_name_exists(pathname, len, ignore_case))
return NULL;
ALLOC_GROW(dir->entries, dir->nr+1, dir->alloc);
return dir->entries[dir->nr++] = dir_entry_new(pathname, len);
}
static struct dir_entry *dir_add_ignored(struct dir_struct *dir, const char *pathname, int len)
{
if (!cache_name_is_other(pathname, len))
return NULL;
ALLOC_GROW(dir->ignored, dir->ignored_nr+1, dir->ignored_alloc);
return dir->ignored[dir->ignored_nr++] = dir_entry_new(pathname, len);
}
enum exist_status {
index_nonexistent = 0,
index_directory,
index_gitdir,
};
/*
* The index sorts alphabetically by entry name, which
* means that a gitlink sorts as '\0' at the end, while
* a directory (which is defined not as an entry, but as
* the files it contains) will sort with the '/' at the
* end.
*/
static enum exist_status directory_exists_in_index(const char *dirname, int len)
{
int pos = cache_name_pos(dirname, len);
if (pos < 0)
pos = -pos-1;
while (pos < active_nr) {
struct cache_entry *ce = active_cache[pos++];
unsigned char endchar;
if (strncmp(ce->name, dirname, len))
break;
endchar = ce->name[len];
if (endchar > '/')
break;
if (endchar == '/')
return index_directory;
if (!endchar && S_ISGITLINK(ce->ce_mode))
return index_gitdir;
}
return index_nonexistent;
}
/*
* When we find a directory when traversing the filesystem, we
* have three distinct cases:
*
* - ignore it
* - see it as a directory
* - recurse into it
*
* and which one we choose depends on a combination of existing
* git index contents and the flags passed into the directory
* traversal routine.
*
* Case 1: If we *already* have entries in the index under that
* directory name, we always recurse into the directory to see
* all the files.
*
* Case 2: If we *already* have that directory name as a gitlink,
* we always continue to see it as a gitlink, regardless of whether
* there is an actual git directory there or not (it might not
* be checked out as a subproject!)
*
* Case 3: if we didn't have it in the index previously, we
* have a few sub-cases:
*
* (a) if "show_other_directories" is true, we show it as
* just a directory, unless "hide_empty_directories" is
* also true and the directory is empty, in which case
* we just ignore it entirely.
* (b) if it looks like a git directory, and we don't have
* 'no_gitlinks' set we treat it as a gitlink, and show it
* as a directory.
* (c) otherwise, we recurse into it.
*/
enum directory_treatment {
show_directory,
ignore_directory,
recurse_into_directory,
};
static enum directory_treatment treat_directory(struct dir_struct *dir,
const char *dirname, int len,
const struct path_simplify *simplify)
{
/* The "len-1" is to strip the final '/' */
switch (directory_exists_in_index(dirname, len-1)) {
case index_directory:
return recurse_into_directory;
case index_gitdir:
if (dir->flags & DIR_SHOW_OTHER_DIRECTORIES)
return ignore_directory;
return show_directory;
case index_nonexistent:
if (dir->flags & DIR_SHOW_OTHER_DIRECTORIES)
break;
if (!(dir->flags & DIR_NO_GITLINKS)) {
unsigned char sha1[20];
if (resolve_gitlink_ref(dirname, "HEAD", sha1) == 0)
return show_directory;
}
return recurse_into_directory;
}
/* This is the "show_other_directories" case */
if (!(dir->flags & DIR_HIDE_EMPTY_DIRECTORIES))
return show_directory;
if (!read_directory_recursive(dir, dirname, len, 1, simplify))
return ignore_directory;
return show_directory;
}
/*
* This is an inexact early pruning of any recursive directory
* reading - if the path cannot possibly be in the pathspec,
* return true, and we'll skip it early.
*/
static int simplify_away(const char *path, int pathlen, const struct path_simplify *simplify)
{
if (simplify) {
for (;;) {
const char *match = simplify->path;
int len = simplify->len;
if (!match)
break;
if (len > pathlen)
len = pathlen;
if (!memcmp(path, match, len))
return 0;
simplify++;
}
return 1;
}
return 0;
}
static int in_pathspec(const char *path, int len, const struct path_simplify *simplify)
{
if (simplify) {
for (; simplify->path; simplify++) {
if (len == simplify->len
&& !memcmp(path, simplify->path, len))
return 1;
}
}
return 0;
}
static int get_index_dtype(const char *path, int len)
{
int pos;
struct cache_entry *ce;
ce = cache_name_exists(path, len, 0);
if (ce) {
if (!ce_uptodate(ce))
return DT_UNKNOWN;
if (S_ISGITLINK(ce->ce_mode))
return DT_DIR;
/*
* Nobody actually cares about the
* difference between DT_LNK and DT_REG
*/
return DT_REG;
}
/* Try to look it up as a directory */
pos = cache_name_pos(path, len);
if (pos >= 0)
return DT_UNKNOWN;
pos = -pos-1;
while (pos < active_nr) {
ce = active_cache[pos++];
if (strncmp(ce->name, path, len))
break;
if (ce->name[len] > '/')
break;
if (ce->name[len] < '/')
continue;
if (!ce_uptodate(ce))
break; /* continue? */
return DT_DIR;
}
return DT_UNKNOWN;
}
static int get_dtype(struct dirent *de, const char *path, int len)
{
int dtype = de ? DTYPE(de) : DT_UNKNOWN;
struct stat st;
if (dtype != DT_UNKNOWN)
return dtype;
dtype = get_index_dtype(path, len);
if (dtype != DT_UNKNOWN)
return dtype;
if (lstat(path, &st))
return dtype;
if (S_ISREG(st.st_mode))
return DT_REG;
if (S_ISDIR(st.st_mode))
return DT_DIR;
if (S_ISLNK(st.st_mode))
return DT_LNK;
return dtype;
}
/*
* Read a directory tree. We currently ignore anything but
* directories, regular files and symlinks. That's because git
* doesn't handle them at all yet. Maybe that will change some
* day.
*
* Also, we ignore the name ".git" (even if it is not a directory).
* That likely will not change.
*/
static int read_directory_recursive(struct dir_struct *dir, const char *base, int baselen, int check_only, const struct path_simplify *simplify)
{
DIR *fdir = opendir(*base ? base : ".");
int contents = 0;
if (fdir) {
struct dirent *de;
char path[PATH_MAX + 1];
memcpy(path, base, baselen);
while ((de = readdir(fdir)) != NULL) {
int len, dtype;
int exclude;
if (is_dot_or_dotdot(de->d_name) ||
!strcmp(de->d_name, ".git"))
continue;
len = strlen(de->d_name);
/* Ignore overly long pathnames! */
if (len + baselen + 8 > sizeof(path))
continue;
memcpy(path + baselen, de->d_name, len+1);
len = baselen + len;
if (simplify_away(path, len, simplify))
continue;
dtype = DTYPE(de);
exclude = excluded(dir, path, &dtype);
if (exclude && (dir->flags & DIR_COLLECT_IGNORED)
&& in_pathspec(path, len, simplify))
dir_add_ignored(dir, path,len);
/*
* Excluded? If we don't explicitly want to show
* ignored files, ignore it
*/
if (exclude && !(dir->flags & DIR_SHOW_IGNORED))
continue;
if (dtype == DT_UNKNOWN)
dtype = get_dtype(de, path, len);
/*
* Do we want to see just the ignored files?
* We still need to recurse into directories,
* even if we don't ignore them, since the
* directory may contain files that we do..
*/
if (!exclude && (dir->flags & DIR_SHOW_IGNORED)) {
if (dtype != DT_DIR)
continue;
}
switch (dtype) {
default:
continue;
case DT_DIR:
memcpy(path + len, "/", 2);
len++;
switch (treat_directory(dir, path, len, simplify)) {
case show_directory:
if (exclude != !!(dir->flags
& DIR_SHOW_IGNORED))
continue;
break;
case recurse_into_directory:
contents += read_directory_recursive(dir,
path, len, 0, simplify);
continue;
case ignore_directory:
continue;
}
break;
case DT_REG:
case DT_LNK:
break;
}
contents++;
if (check_only)
goto exit_early;
else
dir_add_name(dir, path, len);
}
exit_early:
closedir(fdir);
}
return contents;
}
static int cmp_name(const void *p1, const void *p2)
{
const struct dir_entry *e1 = *(const struct dir_entry **)p1;
const struct dir_entry *e2 = *(const struct dir_entry **)p2;
return cache_name_compare(e1->name, e1->len,
e2->name, e2->len);
}
/*
* Return the length of the "simple" part of a path match limiter.
*/
static int simple_length(const char *match)
{
int len = -1;
for (;;) {
unsigned char c = *match++;
len++;
if (c == '\0' || is_glob_special(c))
return len;
}
}
static struct path_simplify *create_simplify(const char **pathspec)
{
int nr, alloc = 0;
struct path_simplify *simplify = NULL;
if (!pathspec)
return NULL;
for (nr = 0 ; ; nr++) {
const char *match;
if (nr >= alloc) {
alloc = alloc_nr(alloc);
simplify = xrealloc(simplify, alloc * sizeof(*simplify));
}
match = *pathspec++;
if (!match)
break;
simplify[nr].path = match;
simplify[nr].len = simple_length(match);
}
simplify[nr].path = NULL;
simplify[nr].len = 0;
return simplify;
}
static void free_simplify(struct path_simplify *simplify)
{
free(simplify);
}
int read_directory(struct dir_struct *dir, const char *path, int len, const char **pathspec)
{
struct path_simplify *simplify;
if (has_symlink_leading_path(path, len))
return dir->nr;
simplify = create_simplify(pathspec);
read_directory_recursive(dir, path, len, 0, simplify);
free_simplify(simplify);
qsort(dir->entries, dir->nr, sizeof(struct dir_entry *), cmp_name);
qsort(dir->ignored, dir->ignored_nr, sizeof(struct dir_entry *), cmp_name);
return dir->nr;
}
int file_exists(const char *f)
{
struct stat sb;
return lstat(f, &sb) == 0;
}
/*
* get_relative_cwd() gets the prefix of the current working directory
* relative to 'dir'. If we are not inside 'dir', it returns NULL.
*
* As a convenience, it also returns NULL if 'dir' is already NULL. The
* reason for this behaviour is that it is natural for functions returning
* directory names to return NULL to say "this directory does not exist"
* or "this directory is invalid". These cases are usually handled the
* same as if the cwd is not inside 'dir' at all, so get_relative_cwd()
* returns NULL for both of them.
*
* Most notably, get_relative_cwd(buffer, size, get_git_work_tree())
* unifies the handling of "outside work tree" with "no work tree at all".
*/
char *get_relative_cwd(char *buffer, int size, const char *dir)
{
char *cwd = buffer;
if (!dir)
return NULL;
if (!getcwd(buffer, size))
die_errno("can't find the current directory");
if (!is_absolute_path(dir))
dir = make_absolute_path(dir);
while (*dir && *dir == *cwd) {
dir++;
cwd++;
}
if (*dir)
return NULL;
if (*cwd == '/')
return cwd + 1;
return cwd;
}
int is_inside_dir(const char *dir)
{
char buffer[PATH_MAX];
return get_relative_cwd(buffer, sizeof(buffer), dir) != NULL;
}
int is_empty_dir(const char *path)
{
DIR *dir = opendir(path);
struct dirent *e;
int ret = 1;
if (!dir)
return 0;
while ((e = readdir(dir)) != NULL)
if (!is_dot_or_dotdot(e->d_name)) {
ret = 0;
break;
}
closedir(dir);
return ret;
}
int remove_dir_recursively(struct strbuf *path, int only_empty)
{
DIR *dir = opendir(path->buf);
struct dirent *e;
int ret = 0, original_len = path->len, len;
if (!dir)
return -1;
if (path->buf[original_len - 1] != '/')
strbuf_addch(path, '/');
len = path->len;
while ((e = readdir(dir)) != NULL) {
struct stat st;
if (is_dot_or_dotdot(e->d_name))
continue;
strbuf_setlen(path, len);
strbuf_addstr(path, e->d_name);
if (lstat(path->buf, &st))
; /* fall thru */
else if (S_ISDIR(st.st_mode)) {
if (!remove_dir_recursively(path, only_empty))
continue; /* happy */
} else if (!only_empty && !unlink(path->buf))
continue; /* happy, too */
/* path too long, stat fails, or non-directory still exists */
ret = -1;
break;
}
closedir(dir);
strbuf_setlen(path, original_len);
if (!ret)
ret = rmdir(path->buf);
return ret;
}
void setup_standard_excludes(struct dir_struct *dir)
{
const char *path;
dir->exclude_per_dir = ".gitignore";
path = git_path("info/exclude");
if (!access(path, R_OK))
add_excludes_from_file(dir, path);
if (excludes_file && !access(excludes_file, R_OK))
add_excludes_from_file(dir, excludes_file);
}
int remove_path(const char *name)
{
char *slash;
if (unlink(name) && errno != ENOENT)
return -1;
slash = strrchr(name, '/');
if (slash) {
char *dirs = xstrdup(name);
slash = dirs + (slash - name);
do {
*slash = '\0';
} while (rmdir(dirs) && (slash = strrchr(dirs, '/')));
free(dirs);
}
return 0;
}