X-Git-Url: https://git.danieliu.xyz/?a=blobdiff_plain;f=src%2Fcstack.c;fp=src%2Fcstack.c;h=aafb95f1b1915afde522f74044aa145355cc9ece;hb=6f9f33a6a5c7d677b4f4464218c01580a391cf08;hp=0000000000000000000000000000000000000000;hpb=3abe61887adc463e2d00c000012d1e2cff15f56f;p=smdp.git

diff --git a/src/cstack.c b/src/cstack.c
new file mode 100644
index 0000000..aafb95f
--- /dev/null
+++ b/src/cstack.c
@@ -0,0 +1,67 @@
+/*
+ * An implementation of a char stack in heap memory.
+ * Copyright (C) 2014 Michael Goehler
+ *
+ * This file is part of mdp.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#include <stdlib.h> // malloc, realloc
+
+#include "cstack.h"
+
+cstack_t *cstack_init() {
+    cstack_t *stack = malloc(sizeof(cstack_t));
+    stack->content = (void*)0;
+    stack->alloc = stack->size = 0;
+    stack->head = -1;
+    stack->push = cstack_push;
+    stack->pop = cstack_pop;
+    stack->top = cstack_top;
+    stack->empty = cstack_empty;
+    stack->delete = cstack_delete;
+    return stack;
+}
+
+void cstack_push(cstack_t *self, char c) {
+    if(self->size + sizeof(c) > self->alloc) {
+        self->alloc += (sizeof(char));
+        self->content = realloc(self->content, self->alloc);
+    }
+    self->content[++self->head] = c;
+    self->size += (sizeof(char));
+}
+
+char cstack_pop(cstack_t *self) {
+    self->size -= (sizeof(char));
+    return self->content[self->head--];
+}
+
+int cstack_top(cstack_t *self, char c) {
+    if(self->head >= 0 && self->content[self->head] == c)
+        return 1;
+    return 0;
+}
+
+int cstack_empty(cstack_t *self)  {
+   return self->head == -1;
+}
+
+void cstack_delete(cstack_t *self) {
+    free(self->content);
+    free(self);
+}
+