cstring header + test

diff --git a/Makefile b/Makefile
new file mode 100644 (file)
index 0000000..d318563
--- /dev/null
+++ b/Makefile
@@ -0,0 +1,25 @@
+# set some compiler flags
+CFLAGS=-lncurses
+
+# find *.c in the current directory
+SOURCES=$(wildcard *.c)
+TESTS=$(wildcard test/*.c)
+
+# define the output objects by replacing .c with .o
+TARGETS=$(SOURCES:.c=)
+TEST_TARGETS=$(TESTS:.c=)
+
+# this will make all objects
+all: $(TEST_TARGETS) $(TARGETS) 
+test: $(TEST_TARGETS)
+
+# each objects will be build by a *.c file
+#%.o: %.c
+%: %.c
+       cc $(CFLAGS) -o $@ $^
+
+# this will delete all objects
+# if not all objects are there, they will be compiled first
+clean: $(TARGETS) $(TEST_TARGETS)
+       rm -f $^
+

diff --git a/include/cstring.h b/include/cstring.h
new file mode 100644 (file)
index 0000000..b87bc8d
--- /dev/null
+++ b/include/cstring.h
@@ -0,0 +1,75 @@
+#if !defined( CSTRING_H )
+#define CSTRING_H
+
+/*
+ * A implementation of expandable c strings in heap memory.
+ *
+ * struct: cstring_t which defines a expandable c string type in heap memory
+ *
+ * function: cstring_init to intialize struct of type cstring_t
+ * function: cstring_t->expand to add one character to the string
+ * function: cstring_t->delete to free the allocated memory
+ *
+ * Example:
+ *      cstring_t *p = cstring_init();
+ *      (p->expand)(p, 'X');
+ *      (p->delete)(p);
+ *
+ */
+
+#include <string.h> // strlen
+#include <stdlib.h> // malloc, realloc
+
+// The amount of memory allocated from heap when string expansion hits the
+// allocated memory limit
+#define REALLOC_ADD 10
+
+typedef struct _cstring_t {
+    char *text;
+    size_t size;
+    size_t alloc;
+    void (*expand)(struct _cstring_t *self, char x);
+    void (*expand_arr)(struct _cstring_t *self, char *x);
+    void (*delete)(struct _cstring_t *self);
+} cstring_t;
+
+void cstring_expand(cstring_t *self, char x);
+void cstring_expand_arr(cstring_t *self, char *x);
+void cstring_delete(cstring_t *self);
+
+cstring_t *cstring_init() {
+    cstring_t *x = malloc(sizeof(cstring_t));
+    x->text = (void*)0;
+    x->size = x->alloc = 0;
+    x->expand = cstring_expand;
+    x->expand_arr = cstring_expand_arr;
+    x->delete = cstring_delete;
+    return x;
+}
+
+void cstring_expand(cstring_t *self, char x) {
+    if(self->size + sizeof(x) + sizeof(char) > self->alloc) {
+        self->alloc += (REALLOC_ADD * sizeof(char));
+        self->text = realloc(self->text, self->alloc);
+    }
+    self->text[self->size] = x;
+    self->text[self->size+1] = '\0';
+    self->size = strlen(self->text);
+}
+
+void cstring_expand_arr(cstring_t *self, char *x) {
+    if(self->size + strlen(x) + sizeof(char) > self->alloc) {
+        self->alloc += (REALLOC_ADD * sizeof(char));
+        self->text = realloc(self->text, self->alloc);
+    }
+    self->text = strcat(self->text, x);
+    self->size = strlen(self->text);
+}
+
+
+void cstring_delete(cstring_t *self) {
+    free(self->text);
+    free(self);
+}
+
+#endif // !defined( CSTRING_H )

diff --git a/test/cstring.c b/test/cstring.c
new file mode 100644 (file)
index 0000000..a1d2b2c
--- /dev/null
+++ b/test/cstring.c
@@ -0,0 +1,43 @@
+#include <stdio.h>
+
+#include "../include/cstring.h"
+
+int main(int argc, char *argv[]) {
+
+    // testing with char
+    cstring_t *p = cstring_init();
+    printf("text: %s, size: %i, alloc: %i\n", p->text, p->size, p->alloc);
+
+    (p->expand)(p, 'X'); printf("text: %s, size: %i, alloc: %i\n", p->text, p->size, p->alloc);
+    (p->expand)(p, 'X'); printf("text: %s, size: %i, alloc: %i\n", p->text, p->size, p->alloc);
+    (p->expand)(p, 'X'); printf("text: %s, size: %i, alloc: %i\n", p->text, p->size, p->alloc);
+    (p->expand)(p, 'X'); printf("text: %s, size: %i, alloc: %i\n", p->text, p->size, p->alloc);
+    (p->expand)(p, 'X'); printf("text: %s, size: %i, alloc: %i\n", p->text, p->size, p->alloc);
+    (p->expand)(p, 'X'); printf("text: %s, size: %i, alloc: %i\n", p->text, p->size, p->alloc);
+    (p->expand)(p, 'X'); printf("text: %s, size: %i, alloc: %i\n", p->text, p->size, p->alloc);
+    (p->expand)(p, 'X'); printf("text: %s, size: %i, alloc: %i\n", p->text, p->size, p->alloc);
+    (p->expand)(p, 'X'); printf("text: %s, size: %i, alloc: %i\n", p->text, p->size, p->alloc);
+    (p->expand)(p, 'X'); printf("text: %s, size: %i, alloc: %i\n", p->text, p->size, p->alloc);
+
+    (p->delete)(p);
+
+    // testing with char array
+    p = cstring_init();
+    printf("text: %s, size: %i, alloc: %i\n", p->text, p->size, p->alloc);
+
+    char x[2] = {'X', '\0'};
+
+    (p->expand_arr)(p, x); printf("text: %s, size: %i, alloc: %i\n", p->text, p->size, p->alloc);
+    (p->expand_arr)(p, x); printf("text: %s, size: %i, alloc: %i\n", p->text, p->size, p->alloc);
+    (p->expand_arr)(p, x); printf("text: %s, size: %i, alloc: %i\n", p->text, p->size, p->alloc);
+    (p->expand_arr)(p, x); printf("text: %s, size: %i, alloc: %i\n", p->text, p->size, p->alloc);
+    (p->expand_arr)(p, x); printf("text: %s, size: %i, alloc: %i\n", p->text, p->size, p->alloc);
+    (p->expand_arr)(p, x); printf("text: %s, size: %i, alloc: %i\n", p->text, p->size, p->alloc);
+    (p->expand_arr)(p, x); printf("text: %s, size: %i, alloc: %i\n", p->text, p->size, p->alloc);
+    (p->expand_arr)(p, x); printf("text: %s, size: %i, alloc: %i\n", p->text, p->size, p->alloc);
+    (p->expand_arr)(p, x); printf("text: %s, size: %i, alloc: %i\n", p->text, p->size, p->alloc);
+    (p->expand_arr)(p, x); printf("text: %s, size: %i, alloc: %i\n", p->text, p->size, p->alloc);
+
+    (p->delete)(p);
+}
+