diff options
| -rw-r--r-- | heap_example.c | 59 |
1 files changed, 59 insertions, 0 deletions
diff --git a/heap_example.c b/heap_example.c new file mode 100644 index 0000000..bc587eb --- /dev/null +++ b/heap_example.c @@ -0,0 +1,59 @@ +#include <stdio.h> +#include <stdlib.h> +#include <string.h> + + +int main(int argc, const char *argv[]) +{ + char *char_ptr; + int *int_ptr; + int mem_size; + + if (argc < 2) + mem_size = 50; + else + mem_size = atoi(argv[1]); + + printf("\t[+] allocating %d bytes of memory on the heap for char_ptr\n", mem_size); + char_ptr = (char *) malloc(mem_size); + + if (char_ptr == NULL) { + fprintf(stderr, "error: could not allocate heap memory.\n"); + exit(-1); + } + + strcpy(char_ptr, "this memory is located on the heap."); + printf("char_ptr (%p) --> '%s'\n", char_ptr, char_ptr); + + printf("\t[+] allocating 12 bytes of memory on the heap for int_ptr\n"); + int_ptr = (int *) malloc(12); + + if (int_ptr == NULL) { + fprintf(stderr, "Error: could not allocate heap memory.\n"); + exit(-1); + } + + *int_ptr = 31337; + printf("int_ptr (%p) --> %d\n", int_ptr, *int_ptr); + + printf("\t[-] freeing char_ptr's heap memory...\n"); + free(char_ptr); + + printf("\t[+] allocating another 15 bytes for char_ptr\n"); + char_ptr = (char *)malloc(15); + + if (char_ptr == NULL) { + fprintf(stderr, "Error: could not allocate heap memory.\n"); + exit(-1); + } + + strcpy(char_ptr, "new memory"); + printf("char_ptr (%p) --> '%s'\n", char_ptr, char_ptr); + + printf("\t[-] freeing int_ptr's heap memory...\n"); + free(int_ptr); + printf("\t[-] freeing char_ptr's heap memory...\n"); + free(char_ptr); + + return 0; +} |
