3 files changed, 50 insertions, 29 deletions

diff --git a/lib/lib.c b/lib/lib.c
index 7a3ada4a..1efb642f 100644
--- a/lib/lib.c
+++ b/lib/lib.c
@@ -116,6 +116,55 @@ off_t lskip(int fd, off_t offset)
   return offset;
 }
 
+// flags: 1=make last dir (with mode lastmode, otherwise skips last component)
+//        2=make path (already exists is ok)
+//        4=verbose
+// returns 0 = path ok, 1 = error
+int mkpathat(int atfd, char *dir, mode_t lastmode, int flags)
+{
+  struct stat buf;
+  char *s;
+
+  // mkdir -p one/two/three is not an error if the path already exists,
+  // but is if "three" is a file. The others we dereference and catch
+  // not-a-directory along the way, but the last one we must explicitly
+  // test for. Might as well do it up front.
+
+  if (!fstatat(atfd, dir, &buf, 0) && !S_ISDIR(buf.st_mode)) {
+    errno = EEXIST;
+    return 1;
+  }
+
+  // Skip leading / of absolute paths
+  while (*dir == '/') dir++;
+
+  for (s=dir; ;s++) {
+    char save = 0;
+    mode_t mode = (0777&~toys.old_umask)|0300;
+
+    // Skip leading / of absolute paths.
+    if (*s == '/' && (flags&2)) {
+      save = *s;
+      *s = 0;
+    } else if (*s) continue;
+
+    // Use the mode from the -m option only for the last directory.
+    if (!save) {
+      if (flags&1) mode = lastmode;
+      else break;
+    }
+
+    if (mkdirat(atfd, dir, mode)) {
+      if (!(flags&2) || errno != EEXIST) return 1;
+    } else if (flags&4)
+      fprintf(stderr, "%s: created directory '%s'\n", toys.which->name, dir);
+    
+    if (!(*s = save)) break;
+  }
+
+  return 0;
+}
+
 // Split a path into linked list of components, tracking head and tail of list.
 // Filters out // entries with no contents.
 struct string_list **splitpath(char *path, struct string_list **list)
diff --git a/lib/lib.h b/lib/lib.h
index 6355b3e1..56927b8b 100644
--- a/lib/lib.h
+++ b/lib/lib.h
@@ -110,7 +110,6 @@ char *xabspath(char *path, int exact);
 char *xrealpath(char *path);
 void xchdir(char *path);
 void xchroot(char *path);
-void xmkpath(char *path, int mode);
 struct passwd *xgetpwuid(uid_t uid);
 struct group *xgetgrgid(gid_t gid);
 struct passwd *xgetpwnam(char *name);
@@ -128,6 +127,7 @@ void perror_exit(char *msg, ...) noreturn;
 ssize_t readall(int fd, void *buf, size_t len);
 ssize_t writeall(int fd, void *buf, size_t len);
 off_t lskip(int fd, off_t offset);
+int mkpathat(int atfd, char *dir, mode_t lastmode, int flags);
 struct string_list **splitpath(char *path, struct string_list **list);
 char *readfile(char *name, char *buf, off_t len);
 void msleep(long miliseconds);
diff --git a/lib/xwrap.c b/lib/xwrap.c
index 2ecffaad..51bd2b43 100644
--- a/lib/xwrap.c
+++ b/lib/xwrap.c
@@ -369,34 +369,6 @@ void xchroot(char *path)
   xchdir("/");
 }
 
-// Ensure entire path exists.
-// If mode != -1 set permissions on newly created dirs.
-// Requires that path string be writable (for temporary null terminators).
-void xmkpath(char *path, int mode)
-{
-  char *p, old;
-  mode_t mask;
-  int rc;
-  struct stat st;
-
-  for (p = path; ; p++) {
-    if (!*p || *p == '/') {
-      old = *p;
-      *p = rc = 0;
-      if (stat(path, &st) || !S_ISDIR(st.st_mode)) {
-        if (mode != -1) {
-          mask=umask(0);
-          rc = mkdir(path, mode);
-          umask(mask);
-        } else rc = mkdir(path, 0777);
-      }
-      *p = old;
-      if(rc) perror_exit("mkpath '%s'", path);
-    }
-    if (!*p) break;
-  }
-}
-
 struct passwd *xgetpwuid(uid_t uid)
 {
   struct passwd *pwd = getpwuid(uid);