libpwdgrp: fixes suggested by Tito, comment tweaks

function                                             old     new   delta
bb_internal_getpwent_r                               100     121     +21
parse_common                                         202     203      +1

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

diff --git a/libpwdgrp/pwd_grp.c b/libpwdgrp/pwd_grp.c
index 3b96cc4d68882e7652fb8677281dbaf9e728ecca..524acfeab916937130746295554719b478115975 100644 (file)
--- a/libpwdgrp/pwd_grp.c
+++ b/libpwdgrp/pwd_grp.c
@@ -9,13 +9,13 @@
  * Rewrite of some parts. Main differences are:
  *
  * 1) the buffer for getpwuid, getgrgid, getpwnam, getgrnam is dynamically
- *    allocated and reused by later calls.
+ *    allocated.
  *    If ENABLE_FEATURE_CLEAN_UP is set the buffers are freed at program
  *    exit using the atexit function to make valgrind happy.
  * 2) the passwd/group files:
  *      a) must contain the expected number of fields (as per count of field
  *         delimeters ":") or we will complain with a error message.
- *      b) leading or trailing whitespace in fields is stripped.
+ *      b) leading and trailing whitespace in fields is stripped.
  *      c) some fields are not allowed to be empty (e.g. username, uid/gid,
  *         homedir, shell) and in this case NULL is returned and errno is
  *         set to EINVAL. This behaviour could be easily changed by
@@ -23,7 +23,7 @@
  *         makes a field mandatory).
  *      d) the string representing uid/gid must be convertible by strtoXX
  *         functions, or errno is set to EINVAL.
- *      e) leading or trailing whitespace in group member names are stripped.
+ *      e) leading and trailing whitespace in group member names is stripped.
  * 3) the internal function for getgrouplist uses dynamically allocated buffer.
  * 4) at the moment only the functions really used by busybox code are
  *    implemented, if you need a particular missing function it should be
@@ -34,15 +34,15 @@
 
 struct const_passdb {
        const char *filename;
-       const char def[7 + 2*ENABLE_USE_BB_SHADOW];
-       const uint8_t off[7 + 2*ENABLE_USE_BB_SHADOW];
+       char def[7 + 2*ENABLE_USE_BB_SHADOW];
+       uint8_t off[7 + 2*ENABLE_USE_BB_SHADOW];
        uint8_t numfields;
        uint8_t size_of;
 };
 struct passdb {
        const char *filename;
-       const char def[7 + 2*ENABLE_USE_BB_SHADOW];
-       const uint8_t off[7 + 2*ENABLE_USE_BB_SHADOW];
+       char def[7 + 2*ENABLE_USE_BB_SHADOW];
+       uint8_t off[7 + 2*ENABLE_USE_BB_SHADOW];
        uint8_t numfields;
        uint8_t size_of;
        FILE *fp;
@@ -105,7 +105,7 @@ static const struct const_passdb const_sp_db = {
 
 /* We avoid having big global data. */
 struct statics {
-       /* It's ok to use same buffer (db[0].malloced) for getpwuid and getpwnam.
+       /* We use same buffer (db[0].malloced) for getpwuid and getpwnam.
         * Manpage says:
         * "The return value may point to a static area, and may be overwritten
         * by subsequent calls to getpwent(), getpwnam(), or getpwuid()."
@@ -203,7 +203,7 @@ static char *parse_common(FILE *fp, struct passdb *db,
                        goto free_and_next;
                }
 
-               if (!key) {
+               if (field_pos == -1) {
                        /* no key specified: sequential read, return a record */
                        break;
                }
@@ -292,7 +292,6 @@ static void *convert_to_struct(struct passdb *db,
                                ( ((intptr_t)S.tokenize_end + sizeof(members[0]))
                                & -(intptr_t)sizeof(members[0])
                                );
-
                        ((struct group *)result)->gr_mem = members;
                        while (--i >= 0) {
                                if (buffer[0]) {
@@ -391,7 +390,9 @@ static int FAST_FUNC getXXent_r(uintptr_t db_idx, char *buffer, size_t buflen,
                close_on_exec_on(fileno(db->fp));
        }
 
-       buf = parse_common(db->fp, db, /*no search key:*/ NULL, 0);
+       buf = parse_common(db->fp, db, /*no search key:*/ NULL, -1);
+       if (!buf && !errno)
+               errno = ENOENT;
        return massage_data_for_r_func(db, buffer, buflen, result, buf);
 }
 
@@ -493,7 +494,7 @@ static gid_t* FAST_FUNC getgrouplist_internal(int *ngroups_ptr,
        if (fp) {
                struct passdb *db = &get_S()->db[1];
                char *buf;
-               while ((buf = parse_common(fp, db, NULL, 0)) != NULL) {
+               while ((buf = parse_common(fp, db, NULL, -1)) != NULL) {
                        char **m;
                        struct group group;
                        if (!convert_to_struct(db, buf, &group))
@@ -505,7 +506,7 @@ static gid_t* FAST_FUNC getgrouplist_internal(int *ngroups_ptr,
                                        continue;
                                group_list = xrealloc_vector(group_list, /*8=2^3:*/ 3, ngroups);
                                group_list[ngroups++] = group.gr_gid;
-                               break;
+                               goto next;
                        }
  next:
                        free(buf);