src/printf.c

Wed, 01 Feb 2023 18:06:50 +0100

author
Mike Becker <universe@uap-core.de>
date
Wed, 01 Feb 2023 18:06:50 +0100
changeset 643
5700ba9154ab
parent 634
f78d3b77d456
child 644
fcaa0891ef28
permissions
-rw-r--r--

#228 make buffer sizes adjustable at compile time

     1 /*
     2  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
     3  *
     4  * Copyright 2021 Mike Becker, Olaf Wintermann All rights reserved.
     5  *
     6  * Redistribution and use in source and binary forms, with or without
     7  * modification, are permitted provided that the following conditions are met:
     8  *
     9  *   1. Redistributions of source code must retain the above copyright
    10  *      notice, this list of conditions and the following disclaimer.
    11  *
    12  *   2. Redistributions in binary form must reproduce the above copyright
    13  *      notice, this list of conditions and the following disclaimer in the
    14  *      documentation and/or other materials provided with the distribution.
    15  *
    16  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
    17  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
    18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
    19  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
    20  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
    21  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
    22  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
    23  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
    24  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
    25  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
    26  * POSSIBILITY OF SUCH DAMAGE.
    27  */
    29 #include "cx/printf.h"
    31 #include <stdio.h>
    32 #include <string.h>
    34 #ifndef CX_PRINTF_SBO_SIZE
    35 #define CX_PRINTF_SBO_SIZE 512
    36 #endif
    38 int cx_fprintf(
    39         void *stream,
    40         cx_write_func wfc,
    41         char const *fmt,
    42         ...
    43 ) {
    44     int ret;
    45     va_list ap;
    46     va_start(ap, fmt);
    47     ret = cx_vfprintf(stream, wfc, fmt, ap);
    48     va_end(ap);
    49     return ret;
    50 }
    52 int cx_vfprintf(void *stream, cx_write_func wfc, char const *fmt, va_list ap) {
    53     char buf[CX_PRINTF_SBO_SIZE];
    54     va_list ap2;
    55     va_copy(ap2, ap);
    56     int ret = vsnprintf(buf, CX_PRINTF_SBO_SIZE, fmt, ap);
    57     if (ret < 0) {
    58         return ret;
    59     } else if (ret < CX_PRINTF_SBO_SIZE) {
    60         return (int) wfc(buf, 1, ret, stream);
    61     } else {
    62         int len = ret + 1;
    63         char *newbuf = malloc(len);
    64         if (!newbuf) {
    65             return -1;
    66         }
    68         ret = vsnprintf(newbuf, len, fmt, ap2);
    69         if (ret > 0) {
    70             ret = (int) wfc(newbuf, 1, ret, stream);
    71         }
    72         free(newbuf);
    73     }
    74     return ret;
    75 }
    77 cxmutstr cx_asprintf_a(CxAllocator *allocator, char const *fmt, ...) {
    78     va_list ap;
    79     cxmutstr ret;
    80     va_start(ap, fmt);
    81     ret = cx_vasprintf_a(allocator, fmt, ap);
    82     va_end(ap);
    83     return ret;
    84 }
    86 cxmutstr cx_vasprintf_a(CxAllocator *a, char const *fmt, va_list ap) {
    87     cxmutstr s;
    88     s.ptr = NULL;
    89     s.length = 0;
    90     char buf[CX_PRINTF_SBO_SIZE];
    91     va_list ap2;
    92     va_copy(ap2, ap);
    93     int ret = vsnprintf(buf, CX_PRINTF_SBO_SIZE, fmt, ap);
    94     if (ret > 0 && ret < CX_PRINTF_SBO_SIZE) {
    95         s.ptr = cxMalloc(a, ret + 1);
    96         if (s.ptr) {
    97             s.length = (size_t) ret;
    98             memcpy(s.ptr, buf, ret);
    99             s.ptr[s.length] = '\0';
   100         }
   101     } else {
   102         int len = ret + 1;
   103         s.ptr = cxMalloc(a, len);
   104         if (s.ptr) {
   105             ret = vsnprintf(s.ptr, len, fmt, ap2);
   106             if (ret < 0) {
   107                 free(s.ptr);
   108                 s.ptr = NULL;
   109             } else {
   110                 s.length = (size_t) ret;
   111             }
   112         }
   113     }
   114     return s;
   115 }

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