1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150
|
/* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/*
* The ap_vsnprintf/ap_snprintf functions are based on, and used with the
* permission of, the SIO stdio-replacement strx_* functions by Panos
* Tsirigotis <panos@alumni.cs.colorado.edu> for xinetd.
*/
#ifndef APACHE_AP_SNPRINTF_H
#define APACHE_AP_SNPRINTF_H
#include <stdio.h>
#include <stdarg.h>
#include <limits.h>
#ifdef __cplusplus
extern "C" {
#endif
/* stuff marked API_EXPORT is part of the API, and intended for use
* by modules
*/
#ifndef API_EXPORT
#define API_EXPORT(type) type
#endif
/* Stuff marked API_EXPORT_NONSTD is part of the API, and intended for
* use by modules. The difference between API_EXPORT and
* API_EXPORT_NONSTD is that the latter is required for any functions
* which use varargs or are used via indirect function call. This
* is to accomodate the two calling conventions in windows dlls.
*/
#ifndef API_EXPORT_NONSTD
#define API_EXPORT_NONSTD(type) type
#endif
#if !defined(__GNUC__) || __GNUC__ < 2 || \
(__GNUC__ == 2 && __GNUC_MINOR__ < 7) ||\
defined(NEXT)
#define __attribute__(__x)
#endif
/* These macros allow correct support of 8-bit characters on systems which
* support 8-bit characters. Pretty dumb how the cast is required, but
* that's legacy libc for ya. These new macros do not support EOF like
* the standard macros do. Tough.
*/
#define ap_isalpha(c) (isalpha(((unsigned char)(c))))
#define ap_isdigit(c) (isdigit(((unsigned char)(c))))
#define ap_islower(c) (islower(((unsigned char)(c))))
/* ap_vformatter() is a generic printf-style formatting routine
* with some extensions. The extensions are:
*
* %pA takes a struct in_addr *, and prints it as a.b.c.d
* %pI takes a struct sockaddr_in * and prints it as a.b.c.d:port
* %pp takes a void * and outputs it in hex
*
* The %p hacks are to force gcc's printf warning code to skip
* over a pointer argument without complaining. This does
* mean that the ANSI-style %p (output a void * in hex format) won't
* work as expected at all, but that seems to be a fair trade-off
* for the increased robustness of having printf-warnings work.
*
* Additionally, ap_vformatter allows for arbitrary output methods
* using the ap_vformatter_buff and flush_func.
*
* The ap_vformatter_buff has two elements curpos and endpos.
* curpos is where ap_vformatter will write the next byte of output.
* It proceeds writing output to curpos, and updating curpos, until
* either the end of output is reached, or curpos == endpos (i.e. the
* buffer is full).
*
* If the end of output is reached, ap_vformatter returns the
* number of bytes written.
*
* When the buffer is full, the flush_func is called. The flush_func
* can return -1 to indicate that no further output should be attempted,
* and ap_vformatter will return immediately with -1. Otherwise
* the flush_func should flush the buffer in whatever manner is
* appropriate, re-initialize curpos and endpos, and return 0.
*
* Note that flush_func is only invoked as a result of attempting to
* write another byte at curpos when curpos >= endpos. So for
* example, it's possible when the output exactly matches the buffer
* space available that curpos == endpos will be true when
* ap_vformatter returns.
*
* ap_vformatter does not call out to any other code, it is entirely
* self-contained. This allows the callers to do things which are
* otherwise "unsafe". For example, ap_psprintf uses the "scratch"
* space at the unallocated end of a block, and doesn't actually
* complete the allocation until ap_vformatter returns. ap_psprintf
* would be completely broken if ap_vformatter were to call anything
* that used a pool. Similarly http_bprintf() uses the "scratch"
* space at the end of its output buffer, and doesn't actually note
* that the space is in use until it either has to flush the buffer
* or until ap_vformatter returns.
*/
typedef struct {
char *curpos;
char *endpos;
} ap_vformatter_buff;
API_EXPORT(int) ap_vformatter(int (*flush_func)(ap_vformatter_buff *),
ap_vformatter_buff *, const char *fmt, va_list ap);
/* These are snprintf implementations based on ap_vformatter().
*
* Note that various standards and implementations disagree on the return
* value of snprintf, and side-effects due to %n in the formatting string.
* ap_snprintf behaves as follows:
*
* Process the format string until the entire string is exhausted, or
* the buffer fills. If the buffer fills then stop processing immediately
* (so no further %n arguments are processed), and return the buffer
* length. In all cases the buffer is NUL terminated. The return value
* is the number of characters placed in the buffer, excluding the
* terminating NUL. All this implies that, at most, (len-1) characters
* will be copied over; if the return value is >= len, then truncation
* occured.
*
* In no event does ap_snprintf return a negative number.
*/
API_EXPORT_NONSTD(int) ap_snprintf(char *buf, size_t len, const char *format,...)
__attribute__((format(printf,3,4)));
API_EXPORT(int) ap_vsnprintf(char *buf, size_t len, const char *format,
va_list ap);
#ifdef __cplusplus
}
#endif
#endif /* !APACHE_AP_SNPRINTF_H */
|