Modify pw_copy:

[pw-darwin.git] / libutil / pw_util.c

diff --git a/libutil/pw_util.c b/libutil/pw_util.c
index 5eae280e5835c19f1294251a398d0195de23e2b6..1068eff6ea9d38e47ae7fbbebb7999fcf1c24df4 100644 (file)
--- a/libutil/pw_util.c
+++ b/libutil/pw_util.c
@@ -410,18 +410,25 @@ pw_make(const struct passwd *pw)
 }
 
 /*
- * Copy password file from one descriptor to another, replacing or adding
- * a single record on the way.
+ * Copy password file from one descriptor to another, replacing, deleting
+ * or adding a single record on the way.
  */
 int
 pw_copy(int ffd, int tfd, const struct passwd *pw, struct passwd *old_pw)
 {
        char buf[8192], *end, *line, *p, *q, *r, t;
        struct passwd *fpw;
+       const struct passwd *spw;
        size_t len;
        int eof, readlen;
 
-       if ((line = pw_make(pw)) == NULL)
+       spw = pw;
+       if (pw == NULL) {
+               line = NULL;
+               if (old_pw == NULL)
+                       return (-1);
+               spw = old_pw;
+       } else if ((line = pw_make(pw)) == NULL)
                return (-1);
 
        eof = 0;
@@ -489,7 +496,7 @@ pw_copy(int ffd, int tfd, const struct passwd *pw, struct passwd *old_pw)
                 */
 
                *q = t;
-               if (fpw == NULL || strcmp(fpw->pw_name, pw->pw_name) != 0) {
+               if (fpw == NULL || fpw->pw_uid != spw->pw_uid) {
                        /* nope */
                        if (fpw != NULL)
                                free(fpw);
@@ -506,11 +513,15 @@ pw_copy(int ffd, int tfd, const struct passwd *pw, struct passwd *old_pw)
                }
                free(fpw);
 
-               /* it is, replace it */
-               len = strlen(line);
-               if (write(tfd, line, len) != (int)len)
-                       goto err;
-
+               /* it is, replace or remove it */
+               if (line != NULL) {
+                       len = strlen(line);
+                       if (write(tfd, line, len) != (int)len)
+                               goto err;
+               } else {
+                       /* when removed, avoid the \n */
+                       q++;
+               }
                /* we're done, just copy the rest over */
                for (;;) {
                        if (write(tfd, q, end - q) != end - q)
@@ -528,16 +539,22 @@ pw_copy(int ffd, int tfd, const struct passwd *pw, struct passwd *old_pw)
                goto done;
        }
 
-       /* if we got here, we have a new entry */
+       /* if we got here, we didn't find the old entry */
+       if (line == NULL) {
+               errno = ENOENT;
+               goto err;
+       }
        len = strlen(line);
        if ((size_t)write(tfd, line, len) != len ||
            write(tfd, "\n", 1) != 1)
                goto err;
  done:
-       free(line);
+       if (line != NULL)
+               free(line);
        return (0);
  err:
-       free(line);
+       if (line != NULL)
+               free(line);
        return (-1);
 }