added a char stack implementation for later use

diff --git a/Makefile b/Makefile
index 442ddc4..c56f247 100644 (file)
--- a/Makefile
+++ b/Makefile
@@ -1,7 +1,7 @@
 CFLAGS=-g -Wall
 
-tmp: tmp.c cstring.o markdown.o parser.o viewer.o
-       cc $(CFLAGS) -o tmp tmp.c cstring.o markdown.o parser.o viewer.o -lncurses
+tmp: tmp.c cstring.o cstack.o markdown.o parser.o viewer.o
+       cc $(CFLAGS) -o tmp tmp.c cstring.o cstack.o markdown.o parser.o viewer.o -lncurses
 
 viewer.o: viewer.c
        cc $(CFLAGS) -c viewer.c
@@ -12,16 +12,19 @@ parser.o: parser.c
 markdown.o: markdown.c
        cc $(CFLAGS) -c markdown.c
 
+cstack.o: cstack.c
+       cc $(CFLAGS) -c cstack.c
+
 cstring.o: cstring.c
        cc $(CFLAGS) -c cstring.c
 
 all: tmp
 
+clean:
+       rm -f tmp *.o
+
 .PHONY: test
 
 test:
        $(MAKE) -C test
 
-clean:
-       rm -f tmp *.o
-

diff --git a/cstack.c b/cstack.c
new file mode 100644 (file)
index 0000000..6474436
--- /dev/null
+++ b/cstack.c
@@ -0,0 +1,44 @@
+#include <stdlib.h> // malloc, realloc
+
+#include "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--];
+}
+
+char cstack_top(cstack_t *self) {
+    return self->content[self->head];
+}
+
+int cstack_empty(cstack_t *self)  {
+   return self->head == -1;
+}
+
+void cstack_delete(cstack_t *self) {
+    free(self->content);
+    free(self);
+}
+

diff --git a/include/cstack.h b/include/cstack.h
new file mode 100644 (file)
index 0000000..edb9847
--- /dev/null
+++ b/include/cstack.h
@@ -0,0 +1,22 @@
+#if !defined( CSTACK_H )
+#define CSTACK_H
+
+typedef struct _cstack_t {
+    char *content;
+    size_t alloc;
+    size_t size;
+    int head;
+    void (*push)(struct _cstack_t *self, char c);
+    char (*pop)(struct _cstack_t *self);
+    char (*top)(struct _cstack_t *self);
+    int (*empty)(struct _cstack_t *self);
+    void (*delete)(struct _cstack_t *self);
+} cstack_t;
+
+void cstack_push(cstack_t *self, char c);
+char cstack_pop(cstack_t *self);
+char cstack_top(cstack_t *self);
+int cstack_empty(cstack_t *self);
+void cstack_delete(cstack_t *self);
+
+#endif // !defined( CSTACK_H )
\ No newline at end of file

diff --git a/test/cstack.c b/test/cstack.c
new file mode 100644 (file)
index 0000000..cf1b504
--- /dev/null
+++ b/test/cstack.c
@@ -0,0 +1,41 @@
+#include <stdio.h>
+
+#include "../include/cstack.h"
+#include "../cstack.c"
+
+int main(int argc, char *argv[]) {
+
+    cstack_t *s = cstack_init();
+    printf("INIT: head: %d, size: %zu, alloc: %zu\n", s->head, s->size, s->alloc);
+
+    (s->push)(s, 'a');
+    printf("PUSH: char: %c, head: %d, size: %zu, alloc: %zu\n", (s->top)(s), s->head, s->size, s->alloc);
+
+    (s->push)(s, 'b');
+    printf("PUSH: char: %c, head: %d, size: %zu, alloc: %zu\n", (s->top)(s), s->head, s->size, s->alloc);
+
+    (s->push)(s, 'c');
+    printf("PUSH: char: %c, head: %d, size: %zu, alloc: %zu\n", (s->top)(s), s->head, s->size, s->alloc);
+
+    char ch = (s->pop)(s);
+    printf("POP: char: %c, head: %d, size: %zu, alloc: %zu\n", ch, s->head, s->size, s->alloc);
+
+    ch = (s->pop)(s);
+    printf("POP: char: %c, head: %d, size: %zu, alloc: %zu\n", ch, s->head, s->size, s->alloc);
+
+    (s->push)(s, 'd');
+    printf("PUSH: char: %c, head: %d, size: %zu, alloc: %zu\n", (s->top)(s), s->head, s->size, s->alloc);
+
+    (s->push)(s, 'e');
+    printf("PUSH: char: %c, head: %d, size: %zu, alloc: %zu\n", (s->top)(s), s->head, s->size, s->alloc);
+
+    while(s->size > 0) {
+        ch = (s->pop)(s);
+        printf("POP: char: %c, head: %d, size: %zu, alloc: %zu\n", ch, s->head, s->size, s->alloc);
+    }
+
+    (s->delete)(s);
+
+    return(0);
+}
+