1 | #ifndef MYSQL_SERVICE_MY_SNPRINTF_INCLUDED |
2 | /* Copyright (c) 2009, 2012, Oracle and/or its affiliates. All rights reserved. |
3 | |
4 | This program is free software; you can redistribute it and/or modify |
5 | it under the terms of the GNU General Public License as published by |
6 | the Free Software Foundation; version 2 of the License. |
7 | |
8 | This program is distributed in the hope that it will be useful, |
9 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
10 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
11 | GNU General Public License for more details. |
12 | |
13 | You should have received a copy of the GNU General Public License |
14 | along with this program; if not, write to the Free Software |
15 | Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */ |
16 | |
17 | /** |
18 | @file |
19 | my_snprintf service |
20 | |
21 | Portable and limited vsnprintf() implementation. |
22 | |
23 | This is a portable, limited vsnprintf() implementation, with some |
24 | extra features. "Portable" means that it'll produce identical result |
25 | on all platforms (for example, on Windows and Linux system printf %e |
26 | formats the exponent differently, on different systems %p either |
27 | prints leading 0x or not, %s may accept null pointer or crash on |
28 | it). "Limited" means that it does not support all the C89 features. |
29 | But it supports few extensions, not in any standard. |
30 | |
31 | my_vsnprintf(to, n, fmt, ap) |
32 | |
33 | @param[out] to A buffer to store the result in |
34 | @param[in] n Store up to n-1 characters, followed by an end 0 |
35 | @param[in] fmt printf-like format string |
36 | @param[in] ap Arguments |
37 | |
38 | @return a number of bytes written to a buffer *excluding* terminating '\0' |
39 | |
40 | @post |
41 | The syntax of a format string is generally the same: |
42 | % <flag> <width> <precision> <length modifier> <format> |
43 | where everithing but the format is optional. |
44 | |
45 | Three one-character flags are recognized: |
46 | '0' has the standard zero-padding semantics; |
47 | '-' is parsed, but silently ignored; |
48 | '`' (backtick) is only supported for strings (%s) and means that the |
49 | string will be quoted according to MySQL identifier quoting rules. |
50 | |
51 | Both <width> and <precision> can be specified as numbers or '*'. |
52 | If an asterisk is used, an argument of type int is consumed. |
53 | |
54 | <length modifier> can be 'l', 'll', or 'z'. |
55 | |
56 | Supported formats are 's' (null pointer is accepted, printed as |
57 | "(null)"), 'b' (extension, see below), 'c', 'd', 'i', 'u', 'x', 'o', |
58 | 'X', 'p' (works as 0x%x), 'f', 'g', 'M' (extension, see below). |
59 | |
60 | Standard syntax for positional arguments $n is supported. |
61 | |
62 | Extensions: |
63 | |
64 | Flag '`' (backtick): see above. |
65 | |
66 | Format 'b': binary buffer, prints exactly <precision> bytes from the |
67 | argument, without stopping at '\0'. |
68 | |
69 | Format 'M': takes one integer, prints this integer, space, double quote |
70 | error message, double quote. In other words |
71 | printf("%M", n) === printf("%d \"%s\"", n, strerror(n)) |
72 | */ |
73 | |
74 | #ifdef __cplusplus |
75 | extern "C" { |
76 | #endif |
77 | |
78 | #ifndef MYSQL_ABI_CHECK |
79 | #include <stdarg.h> |
80 | #include <stdlib.h> |
81 | #endif |
82 | |
83 | extern struct my_snprintf_service_st { |
84 | size_t (*my_snprintf_type)(char*, size_t, const char*, ...); |
85 | size_t (*my_vsnprintf_type)(char *, size_t, const char*, va_list); |
86 | } *my_snprintf_service; |
87 | |
88 | #ifdef MYSQL_DYNAMIC_PLUGIN |
89 | |
90 | #define my_vsnprintf my_snprintf_service->my_vsnprintf_type |
91 | #define my_snprintf my_snprintf_service->my_snprintf_type |
92 | |
93 | #else |
94 | |
95 | size_t my_snprintf(char* to, size_t n, const char* fmt, ...); |
96 | size_t my_vsnprintf(char *to, size_t n, const char* fmt, va_list ap); |
97 | |
98 | #endif |
99 | |
100 | #ifdef __cplusplus |
101 | } |
102 | #endif |
103 | |
104 | #define MYSQL_SERVICE_MY_SNPRINTF_INCLUDED |
105 | #endif |
106 | |
107 | |