src/printf.c

/*
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
 *
 * Copyright 2021 Mike Becker, Olaf Wintermann All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 *   1. Redistributions of source code must retain the above copyright
 *      notice, this list of conditions and the following disclaimer.
 *
 *   2. Redistributions in binary form must reproduce the above copyright
 *      notice, this list of conditions and the following disclaimer in the
 *      documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

#include "cx/printf.h"

#include <stdio.h>
#include <string.h>

#ifndef CX_PRINTF_SBO_SIZE
#define CX_PRINTF_SBO_SIZE 512
#endif

int cx_fprintf(
        void *stream,
        cx_write_func wfc,
        char const *fmt,
        ...
) {
    int ret;
    va_list ap;
    va_start(ap, fmt);
    ret = cx_vfprintf(stream, wfc, fmt, ap);
    va_end(ap);
    return ret;
}

int cx_vfprintf(
        void *stream,
        cx_write_func wfc,
        char const *fmt,
        va_list ap
) {
    char buf[CX_PRINTF_SBO_SIZE];
    va_list ap2;
    va_copy(ap2, ap);
    int ret = vsnprintf(buf, CX_PRINTF_SBO_SIZE, fmt, ap);
    if (ret < 0) {
        return ret;
    } else if (ret < CX_PRINTF_SBO_SIZE) {
        return (int) wfc(buf, 1, ret, stream);
    } else {
        int len = ret + 1;
        char *newbuf = malloc(len);
        if (!newbuf) {
            return -1;
        }

        ret = vsnprintf(newbuf, len, fmt, ap2);
        if (ret > 0) {
            ret = (int) wfc(newbuf, 1, ret, stream);
        }
        free(newbuf);
    }
    return ret;
}

cxmutstr cx_asprintf_a(
        CxAllocator const *allocator,
        char const *fmt,
        ...
) {
    va_list ap;
    cxmutstr ret;
    va_start(ap, fmt);
    ret = cx_vasprintf_a(allocator, fmt, ap);
    va_end(ap);
    return ret;
}

cxmutstr cx_vasprintf_a(
        CxAllocator const *a,
        char const *fmt,
        va_list ap
) {
    cxmutstr s;
    s.ptr = NULL;
    s.length = 0;
    char buf[CX_PRINTF_SBO_SIZE];
    va_list ap2;
    va_copy(ap2, ap);
    int ret = vsnprintf(buf, CX_PRINTF_SBO_SIZE, fmt, ap);
    if (ret > 0 && ret < CX_PRINTF_SBO_SIZE) {
        s.ptr = cxMalloc(a, ret + 1);
        if (s.ptr) {
            s.length = (size_t) ret;
            memcpy(s.ptr, buf, ret);
            s.ptr[s.length] = '\0';
        }
    } else {
        int len = ret + 1;
        s.ptr = cxMalloc(a, len);
        if (s.ptr) {
            ret = vsnprintf(s.ptr, len, fmt, ap2);
            if (ret < 0) {
                free(s.ptr);
                s.ptr = NULL;
            } else {
                s.length = (size_t) ret;
            }
        }
    }
    return s;
}