From e61044d99ce1e68057fda236f04a731f1f3f299a Mon Sep 17 00:00:00 2001
From: Michal Zidek <mzidek@redhat.com>
Date: Wed, 14 Aug 2013 18:01:30 +0200
Subject: [PATCH 2/4] mmap_cache: Remove triple checks in client code.

We had pattern in client code with 3 conditions
that can be replaced with one.
---
 src/sss_client/nss_mc_group.c  | 30 ++++++++++--------------------
 src/sss_client/nss_mc_passwd.c | 30 ++++++++++--------------------
 2 files changed, 20 insertions(+), 40 deletions(-)

diff --git a/src/sss_client/nss_mc_group.c b/src/sss_client/nss_mc_group.c
index da5da0411e556c30c4a3db6faf80139d65ae817c..9fe72a60e58e0c94f0c38f243276060b70f28aa9 100644
--- a/src/sss_client/nss_mc_group.c
+++ b/src/sss_client/nss_mc_group.c
@@ -117,16 +117,11 @@ errno_t sss_nss_mc_getgrnam(const char *name, size_t name_len,
     /* hashes are calculated including the NULL terminator */
     hash = sss_nss_mc_hash(&gr_mc_ctx, name, name_len + 1);
     slot = gr_mc_ctx.hash_table[hash];
-    if (slot > MC_SIZE_TO_SLOTS(gr_mc_ctx.dt_size)) {
-        return ENOENT;
-    }
-
-    while (slot != MC_INVALID_VAL) {
-        if (slot > MC_SIZE_TO_SLOTS(gr_mc_ctx.dt_size)) {
-            /* This probably means that the memory cache was corrupted. */
-            return ENOENT;
-        }
 
+    /* If slot is not within the bounds of mmaped region and
+     * it's value is not MC_INVALID_VAL, then the cache is
+     * probbably corrupted. */
+    while (slot < MC_SIZE_TO_SLOTS(gr_mc_ctx.dt_size)) {
         ret = sss_nss_mc_get_record(&gr_mc_ctx, slot, &rec);
         if (ret) {
             goto done;
@@ -160,7 +155,7 @@ errno_t sss_nss_mc_getgrnam(const char *name, size_t name_len,
         slot = rec->next;
     }
 
-    if (slot == MC_INVALID_VAL) {
+    if (slot >= MC_SIZE_TO_SLOTS(gr_mc_ctx.dt_size)) {
         ret = ENOENT;
         goto done;
     }
@@ -197,16 +192,11 @@ errno_t sss_nss_mc_getgrgid(gid_t gid,
     /* hashes are calculated including the NULL terminator */
     hash = sss_nss_mc_hash(&gr_mc_ctx, gidstr, len+1);
     slot = gr_mc_ctx.hash_table[hash];
-    if (slot > MC_SIZE_TO_SLOTS(gr_mc_ctx.dt_size)) {
-        return ENOENT;
-    }
-
-    while (slot != MC_INVALID_VAL) {
-        if (slot > MC_SIZE_TO_SLOTS(gr_mc_ctx.dt_size)) {
-            /* This probably means that the memory cache was corrupted. */
-            return ENOENT;
-        }
 
+    /* If slot is not within the bounds of mmaped region and
+     * it's value is not MC_INVALID_VAL, then the cache is
+     * probbably corrupted. */
+    while (slot < MC_SIZE_TO_SLOTS(gr_mc_ctx.dt_size)) {
         ret = sss_nss_mc_get_record(&gr_mc_ctx, slot, &rec);
         if (ret) {
             goto done;
@@ -227,7 +217,7 @@ errno_t sss_nss_mc_getgrgid(gid_t gid,
         slot = rec->next;
     }
 
-    if (slot == MC_INVALID_VAL) {
+    if (slot >= MC_SIZE_TO_SLOTS(gr_mc_ctx.dt_size)) {
         ret = ENOENT;
         goto done;
     }
diff --git a/src/sss_client/nss_mc_passwd.c b/src/sss_client/nss_mc_passwd.c
index 4b08766857d5013e6f13c3dbe574c5a88fa915b0..7aca4a04b6b19b50b883960229083b688639ee4f 100644
--- a/src/sss_client/nss_mc_passwd.c
+++ b/src/sss_client/nss_mc_passwd.c
@@ -118,16 +118,11 @@ errno_t sss_nss_mc_getpwnam(const char *name, size_t name_len,
     /* hashes are calculated including the NULL terminator */
     hash = sss_nss_mc_hash(&pw_mc_ctx, name, name_len + 1);
     slot = pw_mc_ctx.hash_table[hash];
-    if (slot > MC_SIZE_TO_SLOTS(pw_mc_ctx.dt_size)) {
-        return ENOENT;
-    }
-
-    while (slot != MC_INVALID_VAL) {
-        if (slot > MC_SIZE_TO_SLOTS(pw_mc_ctx.dt_size)) {
-            /* This probably means that the memory cache was corrupted */
-            return ENOENT;
-        }
 
+    /* If slot is not within the bounds of mmaped region and
+     * it's value is not MC_INVALID_VAL, then the cache is
+     * probbably corrupted. */
+    while (slot < MC_SIZE_TO_SLOTS(pw_mc_ctx.dt_size)) {
         ret = sss_nss_mc_get_record(&pw_mc_ctx, slot, &rec);
         if (ret) {
             goto done;
@@ -162,7 +157,7 @@ errno_t sss_nss_mc_getpwnam(const char *name, size_t name_len,
         slot = rec->next;
     }
 
-    if (slot == MC_INVALID_VAL) {
+    if (slot >= MC_SIZE_TO_SLOTS(pw_mc_ctx.dt_size)) {
         ret = ENOENT;
         goto done;
     }
@@ -199,16 +194,11 @@ errno_t sss_nss_mc_getpwuid(uid_t uid,
     /* hashes are calculated including the NULL terminator */
     hash = sss_nss_mc_hash(&pw_mc_ctx, uidstr, len+1);
     slot = pw_mc_ctx.hash_table[hash];
-    if (slot > MC_SIZE_TO_SLOTS(pw_mc_ctx.dt_size)) {
-        return ENOENT;
-    }
-
-    while (slot != MC_INVALID_VAL) {
-        if (slot > MC_SIZE_TO_SLOTS(pw_mc_ctx.dt_size)) {
-            /* This probably means that the memory cache was corrupted */
-            return ENOENT;
-        }
 
+    /* If slot is not within the bounds of mmaped region and
+     * it's value is not MC_INVALID_VAL, then the cache is
+     * probbably corrupted. */
+    while (slot < MC_SIZE_TO_SLOTS(pw_mc_ctx.dt_size)) {
         ret = sss_nss_mc_get_record(&pw_mc_ctx, slot, &rec);
         if (ret) {
             goto done;
@@ -229,7 +219,7 @@ errno_t sss_nss_mc_getpwuid(uid_t uid,
         slot = rec->next;
     }
 
-    if (slot == MC_INVALID_VAL) {
+    if (slot >= MC_SIZE_TO_SLOTS(pw_mc_ctx.dt_size)) {
         ret = ENOENT;
         goto done;
     }
-- 
1.8.3.1