sstr.h

Go to the documentation of this file.

#ifndef CLOD_SSTR_H
#define CLOD_SSTR_H
 
#include <clod/lib.h>
#include <stddef.h>
#include <string.h>

typedef struct {
    char *ptr;
    size_t size;
} clod_sstr;
 
// Create a sized string from char array and size. The string retains ptr_v.
#define clod_sstr(ptr_v, size_v) ((clod_sstr){ .ptr = (char*)(ptr_v), .size = (size_v) })
// Null string value
#define CLOD_SSTR_NULL ((clod_sstr){ .ptr = nullptr, .size = 0 })
// C string to sized string. The string retains c_string.
#define CLOD_SSTR_C(c_string) ((clod_sstr){ .ptr = (char*)(c_string), .size = strlen(c_string) })

CLOD_INLINE
static inline bool clod_sstr_eq(const clod_sstr str1, const clod_sstr str2) {
    if (str1.size != str2.size) return false;
    if (str1.ptr == str2.ptr) return true;
    if (str1.ptr == nullptr || str2.ptr == nullptr) return false;
    return memcmp(str1.ptr, str2.ptr, str1.size) == 0;
}

CLOD_INLINE
static inline void clod_sstr_cat(clod_sstr *str1, const clod_sstr str2) {
    if (str2.size == 0) return;
    memcpy(str1->ptr + str1->size, str2.ptr, str2.size);
    str1->size += str2.size;
}

CLOD_INLINE
static inline clod_sstr clod_sstr_contains(const clod_sstr str, const clod_sstr elem) {
    if (str.size < elem.size) return CLOD_SSTR_NULL;
    if (elem.size == 0) return clod_sstr(str.ptr, 0);
 
    for (size_t i = 0; i < str.size - elem.size; i++)
        if (memcmp(str.ptr + i, elem.ptr, elem.size) == 0)
            return clod_sstr(str.ptr + i, elem.size);
 
    return CLOD_SSTR_NULL;
}

CLOD_INLINE
static inline clod_sstr clod_sstr_find(const clod_sstr str, const char elem, ptrdiff_t occurrence) {
    if (occurrence > 0) {
        for (size_t i = 0; i < str.size; i++) {
            if (str.ptr[i] == elem) occurrence--;
            if (occurrence == 0) return clod_sstr(str.ptr + i, str.size - i);
        }
        return CLOD_SSTR_NULL;
    }
 
    if (occurrence < 0) {
        for (size_t i = str.size; i > 0; i--) {
            if (str.ptr[i - 1] == elem) occurrence++;
            if (occurrence == 0) return clod_sstr(str.ptr + i - 1, str.size - i + 1);
        }
        return CLOD_SSTR_NULL;
    }
 
    // occurrence == 0
    return str;
}
 
#endif