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Diffstat (limited to 'include/haproxy/show_flags-t.h')
| -rw-r--r-- | include/haproxy/show_flags-t.h | 99 |
1 files changed, 99 insertions, 0 deletions
diff --git a/include/haproxy/show_flags-t.h b/include/haproxy/show_flags-t.h new file mode 100644 index 0000000..824d771 --- /dev/null +++ b/include/haproxy/show_flags-t.h @@ -0,0 +1,99 @@ +/* + * include/haproxy/show_flags.h + * These are helper macros used to decode flags for debugging + * + * Copyright (C) 2022 Willy Tarreau - w@1wt.eu + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation, version 2.1 + * exclusively. + * + * This library is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with this library; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + */ + +#ifndef _HAPROXY_SHOW_FLAGS_H +#define _HAPROXY_SHOW_FLAGS_H + +/* Only define the macro below if the caller requests it using HA_EXPOSE_FLAGS. + * It will be used by many low-level includes and we don't want to + * include the huge stdio here by default. The macro is used to make a string + * of a set of flags (and handles one flag at a time). It will append into + * <_buf>:<_len> the state of flag <_val> in <_flg>, appending string <_del> as + * delimiters till the last flag is dumped, then updating <_buf> and <_len> + * accordingly. <_nam> is used as the name for value <_val>. <_flg> loses all + * dumped flags. If <_flg> is zero and <_val> is 0, a "0" is reported, this can + * be used as a prologue to the dump. If <_val> contains more than one bit set, + * <_flg>'s hexadecimal output is reported instead of a name. + * + * It is possible to use it to enumerate all flags from right to left so that + * they are easier to check in the code. It will start by executing the optional + * code block in the extra flags (if any) before proceeding with the dump using + * the arguments. It is suggested to locally rename it to a single-char macro + * locally for readability, e.g: + * + * #define _(n, ...) __APPEND_FLAG(buf, len, del, flg, n, #n, __VA_ARGS__) + * _(0); + * _(X_FLAG1, _(X_FLAG2, _(X_FLAG3))); + * _(~0); + * #undef _ + * + * __APPEND_ENUM() works a bit differently in that it takes an additional mask + * to isolate bits to compare to the enum's value, and will remove the mask's + * bits at once in case of match. + */ +#ifdef HA_EXPOSE_FLAGS + +#define __APPEND_FLAG(_buf, _len, _del, _flg, _val, _nam, ...) \ + do { \ + size_t _ret = 0; \ + unsigned int _flg0 = (_flg); \ + do { __VA_ARGS__; } while (0); \ + (_flg) &= ~(unsigned int)(_val); \ + if (!((unsigned int)_val) && !(_flg)) \ + _ret = snprintf(_buf, _len, "0%s", \ + (_flg) ? (_del) : ""); \ + else if ((_flg0) & (_val)) { \ + if ((_val) & ((_val) - 1)) \ + _ret = snprintf(_buf, _len, "%#x%s", \ + (_flg0), (_flg) ? (_del) : ""); \ + else \ + _ret = snprintf(_buf, _len, _nam "%s", \ + (_flg) ? (_del) : ""); \ + } \ + if (_ret < _len) { \ + _len -= _ret; \ + _buf += _ret; \ + } \ + } while (0) + +#define __APPEND_ENUM(_buf, _len, _del, _flg, _msk, _val, _nam, ...) \ + do { \ + size_t _ret = 0; \ + do { __VA_ARGS__; } while (0); \ + if (((_flg) & (_msk)) == (_val)) { \ + (_flg) &= ~(_msk); \ + _ret = snprintf(_buf, _len, _nam "%s", \ + (_flg) ? (_del) : ""); \ + } \ + if (_ret < _len) { \ + _len -= _ret; \ + _buf += _ret; \ + } \ + } while (0) + +#else /* EOF not defined => no stdio, do nothing */ + +#define __APPEND_FLAG(_buf, _len, _del, _flg, _val, _nam, ...) do { } while (0) +#define __APPEND_ENUM(_buf, _len, _del, _flg, _msk, _val, _nam, ...) do { } while (0) + +#endif /* EOF */ + +#endif /* _HAPROXY_SHOW_FLAGS_H */ |