X-Git-Url: https://arthur.barton.de/cgi-bin/gitweb.cgi?p=ngircd-alex.git;a=blobdiff_plain;f=src%2Fngircd%2Farray.c;h=ad4f8dac7cda4a57fd5f57a4901829872900e4ac;hp=d34c00d52ba94b561c488f0b37cdef46722227e9;hb=4102e8fdfea33a5d8c398c98db90914c5dc29610;hpb=b7033e147890b3ad0d7fe1520a1db4e4ce040c7b

diff --git a/src/ngircd/array.c b/src/ngircd/array.c
index d34c00d5..ad4f8dac 100644
--- a/src/ngircd/array.c
+++ b/src/ngircd/array.c
@@ -5,42 +5,35 @@
  * (at your option) any later version.
  * Please read the file COPYING, README and AUTHORS for more information.
  *
- * functions to dynamically allocate arrays.
+ * libarray - dynamically allocate arrays.
  * Copyright (c) 2005 Florian Westphal (westphal@foo.fh-furtwangen.de)
- *
  */
 
-#include "array.h"
+/**
+ * @file
+ * Functions to dynamically allocate arrays.
+ */
 
-static char UNUSED id[] = "$Id: array.c,v 1.8 2005/08/30 13:36:32 fw Exp $";
+#include "array.h"
 
 #include <assert.h>
-
 #include <stdlib.h>
 #include <string.h>
 
 #include "log.h"
 
-#define array_UNUSABLE(x)	( ! x->mem  || (0 == x->allocated) )
+/* Enable more Debug messages in alloc / append / memmove code. */
+/* #define DEBUG_ARRAY */
 
-#define ALIGN_32U(x)		((x | 0x1fU) +1)
-#define ALIGN_1024U(x)		((x | 0x3ffU) +1)
-#define ALIGN_4096U(x)		((x | 0xfffU) +1)
+#define array_UNUSABLE(x)	( !(x)->mem )
 
 
 static bool
 safemult_sizet(size_t a, size_t b, size_t *res)
 {
-	size_t tmp;
-
-	if (!a || !b) {
-		*res = 0;
-		return true;
-	}
-
-	tmp = a * b;
+	size_t tmp = a * b;
 
-	if (tmp / b != a)
+	if (b && (tmp / b != a))
 		return false;
 
 	*res = tmp;
@@ -51,67 +44,42 @@ safemult_sizet(size_t a, size_t b, size_t *res)
 void
 array_init(array *a)
 {
-	assert(a);	
+	assert(a != NULL);
 	a->mem = NULL;
 	a->allocated = 0;
 	a->used = 0;
 }
-	
+
 
 /* if realloc() fails, array_alloc return NULL. otherwise return pointer to elem pos in array */
 void *
 array_alloc(array * a, size_t size, size_t pos)
 {
 	size_t alloc, pos_plus1 = pos + 1;
-	size_t aligned = 0;
 	char *tmp;
 
 	assert(size > 0);
 
-	if (pos_plus1 < pos)
-		return NULL;
-
-	if (!safemult_sizet(size, pos_plus1, &alloc))
+	if (pos_plus1 == 0 || !safemult_sizet(size, pos_plus1, &alloc))
 		return NULL;
 
 	if (a->allocated < alloc) {
-		if (alloc < 128) {
-			aligned = ALIGN_32U(alloc);
-		} else {
-			if (alloc < 4096) {
-				aligned = ALIGN_1024U(alloc);
-			} else {
-				aligned = ALIGN_4096U(alloc);
-			}
-		}
-#ifdef DEBUG
-		Log(LOG_DEBUG, "array_alloc(): rounded %u to %u bytes.", alloc, aligned);
-#endif
-
-		assert(aligned >= alloc);
-
-		if (aligned < alloc)	/* rounding overflow */
-			return NULL;
-
-		alloc = aligned;
-#ifdef DEBUG
+#ifdef DEBUG_ARRAY
 		Log(LOG_DEBUG, "array_alloc(): changing size from %u to %u bytes.",
-		    a->allocated, aligned);
+		    a->allocated, alloc);
 #endif
-
 		tmp = realloc(a->mem, alloc);
 		if (!tmp)
 			return NULL;
 
 		a->mem = tmp;
 		a->allocated = alloc;
-
-		assert(a->allocated > a->used);
-
 		memset(a->mem + a->used, 0, a->allocated - a->used);
-
 		a->used = alloc;
 	}
+
+	assert(a->allocated >= a->used);
+
 	return a->mem + (pos * size);
 }
 
@@ -126,6 +94,7 @@ array_length(const array * const a, size_t membersize)
 	if (array_UNUSABLE(a))
 		return 0;
 
+	assert(a->allocated);
 	return membersize ? a->used / membersize : 0;
 }
 
@@ -137,6 +106,7 @@ array_copy(array * dest, const array * const src)
 	if (array_UNUSABLE(src))
 		return false;
 
+	assert(src->allocated);
 	return array_copyb(dest, src->mem, src->used);
 }
 
@@ -195,7 +165,7 @@ array_catb(array * dest, const char *src, size_t len)
 
 	assert(ptr != NULL);
 
-#ifdef DEBUG
+#ifdef DEBUG_ARRAY
 	Log(LOG_DEBUG,
 	    "array_catb(): appending %u bytes to array (now %u bytes in array).",
 	    len, tmp);
@@ -252,20 +222,22 @@ void *
 array_get(array * a, size_t membersize, size_t pos)
 {
 	size_t totalsize;
+	size_t posplus1 = pos + 1;
 
 	assert(membersize > 0);
 	assert(a != NULL);
 
-	if (array_UNUSABLE(a))
+	if (!posplus1 || array_UNUSABLE(a))
 		return NULL;
 
-	if (!safemult_sizet(pos, membersize, &totalsize))
+	if (!safemult_sizet(posplus1, membersize, &totalsize))
 		return NULL;
 
 	if (a->allocated < totalsize)
 		return NULL;
 
-	return a->mem + pos * membersize;
+	totalsize = pos * membersize;
+	return a->mem + totalsize;
 }
 
 
@@ -273,7 +245,7 @@ void
 array_free(array * a)
 {
 	assert(a != NULL);
-#ifdef DEBUG
+#ifdef DEBUG_ARRAY
 	Log(LOG_DEBUG,
 	    "array_free(): %u bytes free'd (%u bytes still used at time of free()).",
 	    a->allocated, a->used);
@@ -284,17 +256,15 @@ array_free(array * a)
 	a->used = 0;
 }
 
-
 void
-array_free_wipe(array * a)
+array_free_wipe(array *a)
 {
-	if (!array_UNUSABLE(a))
-		memset(a->mem, 0, a->allocated);
-
+	size_t bytes = a->allocated;
+	if (bytes)
+		memset(a->mem, 0, bytes);
 	array_free(a);
 }
 
-
 void *
 array_start(const array * const a)
 {
@@ -333,9 +303,6 @@ array_moveleft(array * a, size_t membersize, size_t pos)
 	assert(a != NULL);
 	assert(membersize > 0);
 
-	if (!pos)
-		return;
-
 	if (!safemult_sizet(membersize, pos, &bytepos)) {
 		a->used = 0;
 		return;
@@ -344,7 +311,7 @@ array_moveleft(array * a, size_t membersize, size_t pos)
 	if (!bytepos)
 		return;	/* nothing to do */
 
-#ifdef DEBUG
+#ifdef DEBUG_ARRAY
 	Log(LOG_DEBUG,
 	    "array_moveleft(): %u bytes used in array, starting at position %u.",
 	    a->used, bytepos);