From: Thadeu Lima de Souza Cascardo <cascardo@cascardo.eti.br>
Date: Sat, 25 Jul 2015 19:09:32 +0000 (-0300)
Subject: Implementa função list_insert
X-Git-Url: http://git.cascardo.eti.br/?p=cascardo%2Fdeclara.git;a=commitdiff_plain;h=67f8d157a91a5bb8b83c1c5f00b93cb5fee36d85

Implementa função list_insert
---

diff --git a/list.c b/list.c
index 00b9f7c..6671b2e 100644
--- a/list.c
+++ b/list.c
@@ -43,6 +43,23 @@ struct list * list_new(void)
 	return list;
 }
 
+static struct list * list_expand(struct list **list)
+{
+	struct list *l = *list;
+	struct list *nlist;
+	size_t len = l->alen * sizeof(struct item);
+	size_t nlen = len * 2;
+	nlist = realloc(l, sizeof(*nlist) + nlen);
+	if (!nlist)
+		goto out;
+	*list = l = nlist;
+	memset(&l->items[l->len], 0, len);
+	l->alen = l->alen * 2;
+	return l;
+out:
+	return NULL;
+}
+
 int list_add(struct list **list, void *val)
 {
 	unsigned int i;
@@ -50,15 +67,9 @@ int list_add(struct list **list, void *val)
 	l->items[l->len].val = val;
 	l->len++;
 	if (l->len == l->alen) {
-		struct list *nlist;
-		size_t len = l->alen * sizeof(struct item);
-		size_t nlen = len * 2;
-		nlist = realloc(l, sizeof(*nlist) + nlen);
-		if (!nlist)
+		l = list_expand(list);
+		if (!l)
 			goto out;
-		*list = l = nlist;
-		memset(&l->items[l->len], 0, len);
-		l->alen = l->alen * 2;
 	}
 	return 0;
 out:
@@ -66,6 +77,26 @@ out:
 	return -1;
 }
 
+int list_insert(struct list **list, int pos, void *val)
+{
+	struct list *l = *list;
+	if (pos > l->len)
+		return -1;
+	if (l->len + 1 == l->alen) {
+		l = list_expand(list);
+		if (!l)
+			goto out;
+	}
+	if (pos < l->len)
+		memmove(&l->items[pos + 1], &l->items[pos],
+			(l->len - pos) * sizeof(struct item));
+	l->items[pos].val = val;
+	l->len++;
+	return 0;
+out:
+	return -1;
+}
+
 void * list_get(struct list *list, int pos)
 {
 	unsigned int i;
diff --git a/list.h b/list.h
index 43fc8e2..cebc3d4 100644
--- a/list.h
+++ b/list.h
@@ -24,6 +24,7 @@ struct list;
 
 struct list * list_new(void);
 int list_add(struct list **list, void *val);
+int list_insert(struct list **list, int pos, void *val);
 void * list_get(struct list *list, int pos);
 void list_free(struct list *list, free_function_t *ifree);