#include "nullpo.hpp"

#include <cstdarg>  // exception to "no va_list" rule
#include <cstdio>
#include <cstring>

static
void nullpo_info_core(const char *file, int line, const char *func);
__attribute__((format(printf, 4, 0)))
static
void nullpo_info_core(const char *file, int line, const char *func,
                              const char *fmt, va_list ap);

/// Null check and print format
bool nullpo_chk_f(const char *file, int line, const char *func,
                   const void *target, const char *fmt, ...)
{
    va_list ap;

    if (target)
        return 0;

    va_start(ap, fmt);
    nullpo_info_core(file, line, func, fmt, ap);
    va_end(ap);
    return 1;
}
bool nullpo_chk(const char *file, int line, const char *func,
                 const void *target)
{
    if (target)
        return 0;

    nullpo_info_core(file, line, func);
    return 1;
}

/// External functions
void nullpo_info_f(const char *file, int line, const char *func,
                    const char *fmt, ...)
{
    va_list ap;

    va_start(ap, fmt);
    nullpo_info_core(file, line, func, fmt, ap);
    va_end(ap);
}
void nullpo_info(const char *file, int line, const char *func)
{
    nullpo_info_core(file, line, func);
}

/// Actual output function
static
void nullpo_info_core(const char *file, int line, const char *func)
{
    if (!file)
        file = "??";
    if (!func || !*func)
        func = "unknown";

    fprintf(stderr, "%s:%d: in func `%s': NULL pointer\n", file, line, func);
}

static
void nullpo_info_core(const char *file, int line, const char *func,
                              const char *fmt, va_list ap)
{
    nullpo_info_core(file, line, func);
    if (fmt && *fmt)
    {
        vfprintf(stderr, fmt, ap);
        if (fmt[strlen(fmt) - 1] != '\n')
            fputc('\n', stderr);
    }
}