From 5ec16e430b066e6b84d1346fa81a87fe352ed3b6 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Farkasv=C3=B6lgyi=20Istv=C3=A1n?= <isty001@gmail.com>
Date: Fri, 14 Apr 2017 12:24:32 +0200
Subject: [PATCH] pool_foreach, readme

---
 README.md            | 24 +++++++++++++++++++++---
 package.json         |  2 +-
 src/mem_pool.c       | 29 +++++++++++++++++++++++------
 src/mem_pool.h       |  9 ++++++++-
 test/mem_pool_test.c | 28 ++++++++++++++++++++++++++++
 5 files changed, 81 insertions(+), 11 deletions(-)

diff --git a/README.md b/README.md
index ee6f97d..e999520 100644
--- a/README.md
+++ b/README.md
@@ -28,13 +28,31 @@ Get a block:
 void *ptr = pool_alloc(pool);
 ```
 
-When not needed anymore, give it back to the pool, and make it reusable:
+You can iterate through all the blocks allocated with the given pool like this:
 
 ```c
-pool_free(pool, ptr1);
+static void callback(void *item)
+{
+    //
+}
+
+pool_foreach(pool, callback);
+```
+
+To check if the block is allocated with the pool:
+
+```c
+if (pool_has_ptr(pool, ptr)) { /* */ }
+```
+
+When not needed anymore, give the pointer back to the pool, and make it reusable. This will return -1
+if the pointer is not known by the pool.
+
+```c
+pool_free(pool, ptr);
 ```
 
-If everything is finished, then actually free all the memory allocated:
+To actually free all the memory allocated:
 
 ```c
 pool_destroy(pool);
diff --git a/package.json b/package.json
index 995f87c..df802d0 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "mem-pool",
-  "version": "0.1.0",
+  "version": "0.2.0",
   "repo": "isty001/mem-pool",
   "description": "Fix member sized, growing memory pool",
   "keywords": [
diff --git a/src/mem_pool.c b/src/mem_pool.c
index 4b92ec1..1a2960a 100644
--- a/src/mem_pool.c
+++ b/src/mem_pool.c
@@ -25,7 +25,8 @@ typedef struct block Block;
 
 
 struct buffer {
-    void *memory;
+    void *start;
+    void *current;
     void *end;
     Buffer *next;
 };
@@ -48,9 +49,10 @@ struct mem_pool {
 static Buffer *new_buffer(MemPool *pool)
 {
     Buffer *buff = malloc(sizeof(Buffer));
-    buff->memory = malloc(pool->buff_size);
+    buff->start = malloc(pool->buff_size);
+    buff->current = buff->start;
     buff->next = NULL;
-    buff->end = buff->memory + pool->buff_size;
+    buff->end = buff->current + pool->buff_size;
 
     return buff;
 }
@@ -93,8 +95,8 @@ static void *from_free_list(MemPool *pool)
 
 static void *from_buffer(MemPool *pool, Buffer *buff)
 {
-    void *ptr = buff->memory;
-    buff->memory += pool->memb_size;
+    void *ptr = buff->current;
+    buff->current += pool->memb_size;
     unlock(pool);
 
     return ptr;
@@ -109,7 +111,7 @@ void *pool_alloc(MemPool *pool)
     }
     Buffer *buff = pool->buff_last;
 
-    if (buff->memory == buff->end) {
+    if (buff->current == buff->end) {
         buff = new_buffer(pool);
         pool->buff_last->next = buff;
         pool->buff_last = buff;
@@ -140,6 +142,21 @@ bool pool_has_ptr(MemPool *pool, void *ptr)
     return false;
 }
 
+void pool_foreach(MemPool *pool, PoolForeach callback)
+{
+    lock(pool);
+
+    Buffer *buff = pool->buff_head;
+
+    while (buff) {
+        for (void *block = buff->start; block < buff->current; block += pool->memb_size) {
+            callback(block);
+        }
+        buff = buff->next;
+    }
+    unlock(pool);
+}
+
 int pool_free(MemPool *pool, void *ptr)
 {
     if (!pool_has_ptr(pool, ptr)) {
diff --git a/src/mem_pool.h b/src/mem_pool.h
index dbdd66e..73b202d 100644
--- a/src/mem_pool.h
+++ b/src/mem_pool.h
@@ -8,6 +8,8 @@
 
 typedef struct mem_pool MemPool;
 
+typedef void (*PoolForeach)(void *block);
+
 
 /**
  * @return a new MemPool, with the given block size. If it runs out of space,
@@ -21,10 +23,15 @@ MemPool *pool_init(size_t block_size, size_t increase_count);
 void *pool_alloc(MemPool *pool);
 
 /**
- * @return true if the pointer was allocated by the Pool
+ * @return true if the block was allocated by the Pool
  */
 bool pool_has_ptr(MemPool *pool, void *ptr);
 
+/**
+ * Iterates through all the blocks allocated with the given pool
+ */
+void pool_foreach(MemPool *pool, PoolForeach callback);
+
 /**
  * Makes the pointer reusable
  */
diff --git a/test/mem_pool_test.c b/test/mem_pool_test.c
index c4b43b7..6e63b8f 100644
--- a/test/mem_pool_test.c
+++ b/test/mem_pool_test.c
@@ -38,9 +38,37 @@ MU_TEST(test_pool)
     pool_destroy(pool);
 }
 
+static int ADDED = 0;
+
+static void add_items(int *item)
+{
+    ADDED += *item;
+}
+
+MU_TEST(test_foreach)
+{
+    MemPool *pool = pool_init(sizeof(int), 2);
+    int *a, *b, *c;
+
+    a = pool_alloc(pool);
+    *a = 100;
+    b = pool_alloc(pool);
+    *b = 200;
+    c = pool_alloc(pool);
+    *c = 50;
+
+    pool_foreach(pool, (PoolForeach) add_items);
+
+    mu_assert_int_eq(350, ADDED);
+
+    pool_destroy(pool);
+}
+
 int main(void)
 {
     MU_RUN_TEST(test_pool);
+    MU_RUN_TEST(test_foreach);
+
     MU_REPORT();
 
     return 0;