-/* vi: set sw=4 ts=4 :*/
/* dirtree.c - Functions for dealing with directory trees.
*
* Copyright 2007 Rob Landley <rob@landley.net>
#include "toys.h"
+int isdotdot(char *name)
+{
+ if (name[0]=='.' && (!name[1] || (name[1]=='.' && !name[2]))) return 1;
+
+ return 0;
+}
+
+// Default callback, filters out "." and ".." except at top level.
+
+int dirtree_notdotdot(struct dirtree *catch)
+{
+ // Should we skip "." and ".."?
+ return (!catch->parent||!isdotdot(catch->name))
+ *(DIRTREE_SAVE|DIRTREE_RECURSE);
+}
+
// Create a dirtree node from a path, with stat and symlink info.
// (This doesn't open directory filehandles yet so as not to exhaust the
-// filehandle space on large trees. handle_callback() does that instead.)
+// filehandle space on large trees, dirtree_handle_callback() does that.)
-struct dirtree *dirtree_add_node(int dirfd, char *name, int symfollow)
+struct dirtree *dirtree_add_node(struct dirtree *parent, char *name, int flags)
{
- struct dirtree *dt = NULL;
- struct stat st;
- char buf[4096];
- int len = 0, linklen = 0;
-
- if (name) {
- if (fstatat(dirfd, name, &st, symfollow ? 0 : AT_SYMLINK_NOFOLLOW))
- goto error;
- if (S_ISLNK(st.st_mode)) {
- if (0>(linklen = readlinkat(dirfd, name, buf, 4095))) goto error;
- buf[linklen++]=0;
- }
- len = strlen(name);
- }
- dt = xzalloc((len = sizeof(struct dirtree)+len+1)+linklen);
- if (name) {
- memcpy(&(dt->st), &st, sizeof(struct stat));
- strcpy(dt->name, name);
-
- if (linklen) {
- dt->symlink = memcpy(len+(char *)dt, buf, linklen);
- dt->data = --linklen;
- }
- }
-
- return dt;
+ struct dirtree *dt = NULL;
+ struct stat st;
+ int len = 0, linklen = 0;
+
+ if (name) {
+ // open code this because haven't got node to call dirtree_parentfd() on yet
+ int fd = parent ? parent->dirfd : AT_FDCWD;
+
+ if (fstatat(fd, name, &st, AT_SYMLINK_NOFOLLOW*!(flags&DIRTREE_SYMFOLLOW)))
+ goto error;
+ if (S_ISLNK(st.st_mode)) {
+ if (0>(linklen = readlinkat(fd, name, libbuf, 4095))) goto error;
+ libbuf[linklen++]=0;
+ }
+ len = strlen(name);
+ }
+ dt = xzalloc((len = sizeof(struct dirtree)+len+1)+linklen);
+ dt->parent = parent;
+ if (name) {
+ memcpy(&(dt->st), &st, sizeof(struct stat));
+ strcpy(dt->name, name);
+
+ if (linklen) dt->symlink = memcpy(len+(char *)dt, libbuf, linklen);
+ }
+
+ return dt;
error:
- perror_msg("%s",name);
- free(dt);
- return 0;
+ if (!(flags&DIRTREE_SHUTUP) && !isdotdot(name)) {
+ char *path = parent ? dirtree_path(parent, 0) : "";
+
+ perror_msg("%s%s%s", path, parent ? "/" : "", name);
+ if (parent) free(path);
+ }
+ if (parent) parent->symlink = (char *)1;
+ free(dt);
+ return 0;
}
// Return path to this node, assembled recursively.
-char *dirtree_path(struct dirtree *node, int *plen)
-{
- char *path;
- int len;
-
- if (!node || !node->name) {
- path = xmalloc(*plen);
- *plen = 0;
- return path;
- }
-
- len = (plen ? *plen : 0)+strlen(node->name)+1;
- path = dirtree_path(node->parent, &len);
- if (len && path[len-1] != '/') path[len++]='/';
- len = (stpcpy(path+len, node->name) - path);
- if (plen) *plen = len;
-
- return path;
-}
-
-// Default callback, filters out "." and "..".
+// Initial call can pass in NULL to plen, or point to an int initialized to 0
+// to return the length of the path, or a value greater than 0 to allocate
+// extra space if you want to append your own text to the string.
-int dirtree_notdotdot(struct dirtree *catch)
+char *dirtree_path(struct dirtree *node, int *plen)
{
- // Should we skip "." and ".."?
- if (catch->name[0]=='.' && (!catch->name[1] ||
- (catch->name[1]=='.' && !catch->name[2])))
- return 0;
-
- return DIRTREE_SAVE|DIRTREE_RECURSE;
+ char *path;
+ int len;
+
+ if (!node) {
+ path = xmalloc(*plen);
+ *plen = 0;
+ return path;
+ }
+
+ len = (plen ? *plen : 0)+strlen(node->name)+1;
+ path = dirtree_path(node->parent, &len);
+ if (len && path[len-1] != '/') path[len++]='/';
+ len = (stpcpy(path+len, node->name) - path);
+ if (plen) *plen = len;
+
+ return path;
}
int dirtree_parentfd(struct dirtree *node)
{
- return node->parent ? node->parent->data : AT_FDCWD;
+ return node->parent ? node->parent->dirfd : AT_FDCWD;
}
-// Handle callback for a node in the tree. Returns saved node(s) or NULL.
-//
-// By default, allocates a tree of struct dirtree, not following symlinks
-// If callback==NULL, or callback always returns 0, allocate tree of struct
-// dirtree and return root of tree. Otherwise call callback(node) on each
-// hit, free structures after use, and return NULL.
-//
+// Handle callback for a node in the tree. Returns saved node(s) if
+// callback returns DIRTREE_SAVE, otherwise frees consumed nodes and
+// returns NULL. If !callback return top node unchanged.
+// If !new return DIRTREE_ABORTVAL
-struct dirtree *handle_callback(struct dirtree *new,
- int (*callback)(struct dirtree *node))
+struct dirtree *dirtree_handle_callback(struct dirtree *new,
+ int (*callback)(struct dirtree *node))
{
- int flags, dir = S_ISDIR(new->st.st_mode);
+ int flags;
- if (!callback) callback = dirtree_notdotdot;
+ if (!new) return DIRTREE_ABORTVAL;
+ if (!callback) return new;
+ flags = callback(new);
- flags = callback(new);
+ if (S_ISDIR(new->st.st_mode) && (flags & (DIRTREE_RECURSE|DIRTREE_COMEAGAIN)))
+ flags = dirtree_recurse(new, callback,
+ openat(dirtree_parentfd(new), new->name, O_CLOEXEC), flags);
- if (dir) {
- if (flags & (DIRTREE_RECURSE|DIRTREE_COMEAGAIN)) {
- new->data = openat(dirtree_parentfd(new), new->name, 0);
- dirtree_recurse(new, callback, flags & DIRTREE_SYMFOLLOW);
- if (flags & DIRTREE_COMEAGAIN) flags = callback(new);
- }
- }
+ // If this had children, it was callback's job to free them already.
+ if (!(flags & DIRTREE_SAVE)) {
+ free(new);
+ new = NULL;
+ }
- // If this had children, it was callback's job to free them already.
- if (!(flags & DIRTREE_SAVE)) {
- free(new);
- new = NULL;
- }
-
- return (flags & DIRTREE_ABORT)==DIRTREE_ABORT ? DIRTREE_ABORTVAL : new;
+ return (flags & DIRTREE_ABORT)==DIRTREE_ABORT ? DIRTREE_ABORTVAL : new;
}
-// Recursively read/process children of directory node (with dirfd in data),
-// filtering through callback().
+// Recursively read/process children of directory node, filtering through
+// callback(). Uses and closes supplied ->dirfd.
-void dirtree_recurse(struct dirtree *node,
- int (*callback)(struct dirtree *node), int symfollow)
+int dirtree_recurse(struct dirtree *node,
+ int (*callback)(struct dirtree *node), int dirfd, int flags)
{
- struct dirtree *new, **ddt = &(node->child);
- struct dirent *entry;
- DIR *dir;
-
- if (!(dir = fdopendir(node->data))) {
- char *path = dirtree_path(node, 0);
- perror_msg("No %s", path);
- free(path);
- close(node->data);
-
- return;
- }
-
- // according to the fddir() man page, the filehandle in the DIR * can still
- // be externally used by things that don't lseek() it.
-
- // The extra parentheses are to shut the stupid compiler up.
- while ((entry = readdir(dir))) {
- if (!(new = dirtree_add_node(node->data, entry->d_name, symfollow)))
- continue;
- new->parent = node;
- new = handle_callback(new, callback);
- if (new == DIRTREE_ABORTVAL) break;
- if (new) {
- *ddt = new;
- ddt = &((*ddt)->next);
- }
- }
-
- // This closes filehandle as well, so note it
- closedir(dir);
- node->data = -1;
+ struct dirtree *new, **ddt = &(node->child);
+ struct dirent *entry;
+ DIR *dir;
+
+ node->dirfd = dirfd;
+ if (node->dirfd == -1 || !(dir = fdopendir(node->dirfd))) {
+ if (!(flags & DIRTREE_SHUTUP)) {
+ char *path = dirtree_path(node, 0);
+ perror_msg("No %s", path);
+ free(path);
+ }
+ close(node->dirfd);
+
+ return flags;
+ }
+
+ // according to the fddir() man page, the filehandle in the DIR * can still
+ // be externally used by things that don't lseek() it.
+
+ // The extra parentheses are to shut the stupid compiler up.
+ while ((entry = readdir(dir))) {
+ if ((flags&DIRTREE_PROC) && !isdigit(*entry->d_name)) continue;
+ if (!(new = dirtree_add_node(node, entry->d_name, flags))) continue;
+ new = dirtree_handle_callback(new, callback);
+ if (new == DIRTREE_ABORTVAL) break;
+ if (new) {
+ *ddt = new;
+ ddt = &((*ddt)->next);
+ }
+ }
+
+ if (flags & DIRTREE_COMEAGAIN) {
+ node->again++;
+ flags = callback(node);
+ }
+
+ // This closes filehandle as well, so note it
+ closedir(dir);
+ node->dirfd = -1;
+
+ return flags;
}
-// Create dirtree from path, using callback to filter nodes.
-// If callback == NULL allocate a tree of struct dirtree nodes and return
-// pointer to root node.
-// symfollow is just for the top of tree, callback return code controls children
+// Create dirtree from path, using callback to filter nodes. If !callback
+// return just the top node. Use dirtree_notdotdot callback to allocate a
+// tree of struct dirtree nodes and return pointer to root node for later
+// processing.
+// Returns DIRTREE_ABORTVAL if path didn't exist (use DIRTREE_SHUTUP to handle
+// error message yourself).
-struct dirtree *dirtree_read(char *path, int (*callback)(struct dirtree *node))
+struct dirtree *dirtree_flagread(char *path, int flags,
+ int (*callback)(struct dirtree *node))
{
- struct dirtree *root = dirtree_add_node(AT_FDCWD, path, 0);
+ return dirtree_handle_callback(dirtree_add_node(0, path, flags), callback);
+}
- return root ? handle_callback(root, callback) : DIRTREE_ABORTVAL;
+// Common case
+struct dirtree *dirtree_read(char *path, int (*callback)(struct dirtree *node))
+{
+ return dirtree_flagread(path, 0, callback);
}
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