utils.c

#include <stdarg.h>
#include <stddef.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include "utils.h"

/*
 * Add a string
 */

int addstrold(char **strp, size_t *strs, const char *format, ...)
{
	va_list val;
	size_t written;


	va_start(val, format);

	written = vsnprintf(*strp, *strs, format, val);
	va_end(val);

	if (written >= *strs)
	{
		// buffer full
		*strs = 0;
		return(1);
	}
	
	*strs = (*strs - written);
	*strp = (*strp + written);
	return(0);
}

int addstr(String *str, const char *format, ...)
{
	va_list val;
	size_t written;
    size_t available;
    char *pos;

    available = str->max - str->len;
    pos = str->text + str->len;


	va_start(val, format);

	written = vsnprintf(pos, available, format, val);
	va_end(val);

	if (written >= available)
	{
		/* buffer full */
		str->text[(str->max)] = 0;
        str->len = str->max;
		return(1);
	}
	
	str->len = str->len + written;
	return(0);
}





/* 
 * Replace troublesome characters in a string with underscores
 * - only use for strings we already know the size of */

void strcpy_nospaces(char *dest, char *src)
{
	static unsigned char allowed[256] = "_________________________________!_#_%__()*+,-.-0123456789_____?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[_]^__abcdefghijklmnopqrstuvwxyz{_}__________________________________________________________________________________________________________________________________";



	while(*src)
	{
		*(dest++) = allowed[(unsigned char) *(src++)];
	}
	*dest = 0;
}



/*
 * convert a (possibly large) integer to a string with unit suffix
 *
 * add the following check to configure.ac
 * AC_SEARCH_LIBS(pow, [c m], AC_DEFINE([HAVE_POW]))
 */

int gauge_to_si(u64 bignum, char **str)
{
	int i = 0;
	u64 tmpll;
	static char units[] = "kMGTPE";

	tmpll = bignum;

	while ((tmpll /= 1000ULL) && (i < (sizeof(units) - 1)))
	{
		i++;
	}

#ifdef HAVE_POW
	if (i)
	{
		return asprintf(str, "%0.2f%c", ((double)bignum / pow(1000, i)), units[i-1]);
	}
    else
    {
		return asprintf(str, "%Ld", bignum);
	}
#else
    return asprintf(str, "%Ld", bignum);
#endif
	
}

static
struct timespec benchmark_start_time;

static
char *benchmark_task;

void benchmark_start(char const *format, ...)
{
    {
        va_list args;
        va_start(args, format);
        int benchmark_task_length = vsnprintf(NULL, 0u, format, args);
        va_end(args);
        benchmark_task = (char*)malloc(benchmark_task_length + 1);
        benchmark_task[benchmark_task_length] = 0;
    }
    {
        va_list args;
        va_start(args, format);
        vsprintf(benchmark_task, format, args);
        va_end(args);
    }
    fprintf(stderr, "[Starting benchmark] %s\n", benchmark_task);
    clock_gettime(CLOCK_MONOTONIC, &benchmark_start_time);
}

void benchmark_end(void)
{
    {
        struct timespec benchmark_end_time;
        clock_gettime(CLOCK_MONOTONIC, &benchmark_end_time);
        fprintf(
            stderr,
            "[Finished benchmark after %f ms] %s\n",
            ((double)benchmark_end_time.tv_sec * 1000.0 + (double)benchmark_end_time.tv_nsec / 1000000.0)
            - ((double)benchmark_start_time.tv_sec * 1000.0 + (double)benchmark_start_time.tv_nsec / 1000000.0),
            benchmark_task
        );
    }
    free(benchmark_task);
}

char *implode(char const *glue, char **pieces)
{
    size_t total_len = 0u;
    char **walk_pieces = pieces;
    while (*walk_pieces != NULL) {
        total_len += strlen(*walk_pieces++);
    }

    ptrdiff_t walk_pieces_diff = walk_pieces - pieces;
    if (walk_pieces_diff >= 2) {
        total_len += strlen(glue) * (size_t)(walk_pieces_diff - 1);
    }

    char *result = (char*)malloc(total_len + 1u);

    if (walk_pieces_diff > 0) {
        strcpy(result, *pieces);
        if (walk_pieces_diff >= 2) {
            char *walk_result = result;
            walk_pieces = pieces + 1;
            while (*walk_pieces != NULL) {
                while (*walk_result) {
                    ++walk_result;
                }
                strcpy(walk_result, glue);

                while (*walk_result) {
                    ++walk_result;
                }
                strcpy(walk_result, *walk_pieces++);
            }
        }
    } else {
        *result = 0;
    }

    return result;
}