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@kevinlynx
Created November 21, 2014 12:35
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#include <stdio.h>
#include <string>
#include <map>
#include <vector>
#include <list>
void ds_str_i(void *p) {
char **raw = (char**)p;
char *s = *raw;
size_t len = *(size_t*)(s - sizeof(size_t) * 3);
printf("str: %s (%zd)\n", s, len);
}
size_t ds_str() {
std::string s = "hello";
ds_str_i(&s);
return s.size();
}
template <typename T>
void ds_vec_i(void *p) {
T *start = *(T**)p;
T *finish = *(T**)((char*)p + sizeof(void*));
T *end_storage = *(T**)((char*)p + 2 * sizeof(void*));
printf("vec size: %ld, avaiable size: %ld\n", finish - start, end_storage - start);
}
size_t ds_vec() {
std::vector<int> vec;
vec.push_back(0x11);
vec.push_back(0x22);
vec.push_back(0x33);
ds_vec_i<int>(&vec);
return vec.size();
}
size_t ds_map() {
std::map<std::string, int> imap;
imap["abc"] = 0xbbb;
return imap.size();
}
#define NEXT(ptr, T) do { \
void *n = *(char**)ptr; \
T val = *(T*)((char**)ptr + 2); \
printf("list item %p val: 0x%x\n", ptr, val); \
ptr = n; \
} while (0)
template <typename T>
void ds_list_i(void *p) {
void *ptr = *(char**)p;
NEXT(ptr, T);
NEXT(ptr, T);
NEXT(ptr, T);
}
size_t ds_list() {
std::list<int> lst;
lst.push_back(0x11);
lst.push_back(0x22);
lst.push_back(0x33);
ds_list_i<int>(&lst);
return lst.size();
}
int main()
{
ds_str();
ds_map();
ds_vec();
ds_list();
return 0;
}
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