mempool.c: renamed from pool.c

To avoid confusion with pools in irep, we renamed region-based memory
manager from pool to mempool.

- rename pool.c to mempool.c
- separate mempool.h
- rename all mrb_pool to mrb_mempool

So if someone is using pool.c functions (I suppose no one does though),
they need to rename all `mrb_pool` to `mrb_mempool` and include
`mruby/mempool.h` header at the top.

src/mempool.c

@@ -1,11 +1,12 @@
 /*
-** pool.c - memory pool
+** mempool.c - memory pool
 **
 ** See Copyright Notice in mruby.h
 */
 
 #include <string.h>
 #include <mruby.h>
+#include <mruby/mempool.h>
 
 /* configuration section */
 /* allocated memory address should be multiple of POOL_ALIGNMENT */
@@ -30,8 +31,8 @@
 #pragma warning(disable : 4200)
 #endif
 
-struct mrb_pool_page {
-  struct mrb_pool_page *next;
+struct mrb_mempool_page {
+  struct mrb_mempool_page *next;
   size_t offset;
   size_t len;
   void *last;
@@ -42,9 +43,9 @@ struct mrb_pool_page {
 #pragma warning(pop)
 #endif
 
-struct mrb_pool {
+struct mrb_mempool {
   mrb_state *mrb;
-  struct mrb_pool_page *pages;
+  struct mrb_mempool_page *pages;
 };
 
 #undef TEST_POOL
@@ -60,10 +61,10 @@ struct mrb_pool {
 #  define ALIGN_PADDING(x) (0)
 #endif
 
-MRB_API mrb_pool*
-mrb_pool_open(mrb_state *mrb)
+MRB_API mrb_mempool*
+mrb_mempool_open(mrb_state *mrb)
 {
-  mrb_pool *pool = (mrb_pool*)mrb_malloc_simple(mrb, sizeof(mrb_pool));
+  mrb_mempool *pool = (mrb_mempool*)mrb_malloc_simple(mrb, sizeof(mrb_mempool));
 
   if (pool) {
     pool->mrb = mrb;
@@ -73,28 +74,28 @@ mrb_pool_open(mrb_state *mrb)
 }
 
 MRB_API void
-mrb_pool_close(mrb_pool *pool)
+mrb_mempool_close(mrb_mempool *pool)
 {
-  struct mrb_pool_page *page;
+  struct mrb_mempool_page *page;
 
   if (!pool) return;
   page = pool->pages;
   while (page) {
-    struct mrb_pool_page *tmp = page;
+    struct mrb_mempool_page *tmp = page;
     page = page->next;
     mrb_free(pool->mrb, tmp);
   }
   mrb_free(pool->mrb, pool);
 }
 
-static struct mrb_pool_page*
-page_alloc(mrb_pool *pool, size_t len)
+static struct mrb_mempool_page*
+page_alloc(mrb_mempool *pool, size_t len)
 {
-  struct mrb_pool_page *page;
+  struct mrb_mempool_page *page;
 
   if (len < POOL_PAGE_SIZE)
     len = POOL_PAGE_SIZE;
-  page = (struct mrb_pool_page*)mrb_malloc_simple(pool->mrb, sizeof(struct mrb_pool_page)+len);
+  page = (struct mrb_mempool_page*)mrb_malloc_simple(pool->mrb, sizeof(struct mrb_mempool_page)+len);
   if (page) {
     page->offset = 0;
     page->len = len;
@@ -104,9 +105,9 @@ page_alloc(mrb_pool *pool, size_t len)
 }
 
 MRB_API void*
-mrb_pool_alloc(mrb_pool *pool, size_t len)
+mrb_mempool_alloc(mrb_mempool *pool, size_t len)
 {
-  struct mrb_pool_page *page;
+  struct mrb_mempool_page *page;
 
   if (!pool) return NULL;
   len += ALIGN_PADDING(len);
@@ -129,13 +130,13 @@ mrb_pool_alloc(mrb_pool *pool, size_t len)
 }
 
 MRB_API void*
-mrb_pool_realloc(mrb_pool *pool, void *p, size_t oldlen, size_t newlen)
+mrb_mempool_realloc(mrb_mempool *pool, void *p, size_t oldlen, size_t newlen)
 {
   if (!pool) return NULL;
   if (newlen < oldlen) return p;
   oldlen += ALIGN_PADDING(oldlen);
   newlen += ALIGN_PADDING(newlen);
-  for (struct mrb_pool_page *page = pool->pages; page; page = page->next) {
+  for (struct mrb_mempool_page *page = pool->pages; page; page = page->next) {
     if (page->last == p) {
       /* if p is a last allocation from the page */
       size_t beg = (char*)p - page->page;
@@ -152,7 +153,7 @@ mrb_pool_realloc(mrb_pool *pool, void *p, size_t oldlen, size_t newlen)
       return p;
     }
   }
-  void *np = mrb_pool_alloc(pool, newlen);
+  void *np = mrb_mempool_alloc(pool, newlen);
   if (np == NULL) {
     return NULL;
   }
@@ -165,17 +166,17 @@ int
 main(void)
 {
   int i, len = 250;
-  mrb_pool *pool;
+  mrb_mempool *pool;
   void *p;
 
-  pool = mrb_pool_open(NULL);
-  p = mrb_pool_alloc(pool, len);
+  pool = mrb_mempool_open(NULL);
+  p = mrb_mempool_alloc(pool, len);
   for (i=1; i<20; i++) {
     printf("%p (len=%d)\n", p, len);
-    p = mrb_pool_realloc(pool, p, len, len*2);
+    p = mrb_mempool_realloc(pool, p, len, len*2);
     len *= 2;
   }
-  mrb_pool_close(pool);
+  mrb_mempool_close(pool);
   return 0;
 }
 #endif