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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-28 09:35:11 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-28 09:35:11 +0000 |
commit | da76459dc21b5af2449af2d36eb95226cb186ce2 (patch) | |
tree | 542ebb3c1e796fac2742495b8437331727bbbfa0 /include/import/ist.h | |
parent | Initial commit. (diff) | |
download | haproxy-da76459dc21b5af2449af2d36eb95226cb186ce2.tar.xz haproxy-da76459dc21b5af2449af2d36eb95226cb186ce2.zip |
Adding upstream version 2.6.12.upstream/2.6.12upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r-- | include/import/ist.h | 909 |
1 files changed, 909 insertions, 0 deletions
diff --git a/include/import/ist.h b/include/import/ist.h new file mode 100644 index 0000000..978fb3c --- /dev/null +++ b/include/import/ist.h @@ -0,0 +1,909 @@ +/* + * include/import/ist.h + * Very simple indirect string manipulation functions. + * + * Copyright (C) 2014-2020 Willy Tarreau - w@1wt.eu + * + * Permission is hereby granted, free of charge, to any person obtaining + * a copy of this software and associated documentation files (the + * "Software"), to deal in the Software without restriction, including + * without limitation the rights to use, copy, modify, merge, publish, + * distribute, sublicense, and/or sell copies of the Software, and to + * permit persons to whom the Software is furnished to do so, subject to + * the following conditions: + * + * The above copyright notice and this permission notice shall be + * included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES + * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT + * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, + * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR + * OTHER DEALINGS IN THE SOFTWARE. + */ + +#ifndef _IMPORT_IST_H +#define _IMPORT_IST_H + +#include <sys/types.h> +#include <ctype.h> +#include <stddef.h> +#include <string.h> + +#ifndef IST_FREESTANDING +#include <stdlib.h> +#endif + +/* ASCII to lower case conversion table */ +#define _IST_LC ((const unsigned char[256]){ \ + 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, \ + 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f, \ + 0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17, \ + 0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f, \ + 0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27, \ + 0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f, \ + 0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37, \ + 0x38, 0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0x3e, 0x3f, \ + 0x40, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67, \ + 0x68, 0x69, 0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 0x6f, \ + 0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77, \ + 0x78, 0x79, 0x7a, 0x5b, 0x5c, 0x5d, 0x5e, 0x5f, \ + 0x60, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67, \ + 0x68, 0x69, 0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 0x6f, \ + 0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77, \ + 0x78, 0x79, 0x7a, 0x7b, 0x7c, 0x7d, 0x7e, 0x7f, \ + 0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87, \ + 0x88, 0x89, 0x8a, 0x8b, 0x8c, 0x8d, 0x8e, 0x8f, \ + 0x90, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, \ + 0x98, 0x99, 0x9a, 0x9b, 0x9c, 0x9d, 0x9e, 0x9f, \ + 0xa0, 0xa1, 0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa7, \ + 0xa8, 0xa9, 0xaa, 0xab, 0xac, 0xad, 0xae, 0xaf, \ + 0xb0, 0xb1, 0xb2, 0xb3, 0xb4, 0xb5, 0xb6, 0xb7, \ + 0xb8, 0xb9, 0xba, 0xbb, 0xbc, 0xbd, 0xbe, 0xbf, \ + 0xc0, 0xc1, 0xc2, 0xc3, 0xc4, 0xc5, 0xc6, 0xc7, \ + 0xc8, 0xc9, 0xca, 0xcb, 0xcc, 0xcd, 0xce, 0xcf, \ + 0xd0, 0xd1, 0xd2, 0xd3, 0xd4, 0xd5, 0xd6, 0xd7, \ + 0xd8, 0xd9, 0xda, 0xdb, 0xdc, 0xdd, 0xde, 0xdf, \ + 0xe0, 0xe1, 0xe2, 0xe3, 0xe4, 0xe5, 0xe6, 0xe7, \ + 0xe8, 0xe9, 0xea, 0xeb, 0xec, 0xed, 0xee, 0xef, \ + 0xf0, 0xf1, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, \ + 0xf8, 0xf9, 0xfa, 0xfb, 0xfc, 0xfd, 0xfe, 0xff, \ +}) + +/* ASCII to upper case conversion table */ +#define _IST_UC ((const unsigned char[256]){ \ + 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, \ + 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f, \ + 0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17, \ + 0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f, \ + 0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27, \ + 0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f, \ + 0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37, \ + 0x38, 0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0x3e, 0x3f, \ + 0x40, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47, \ + 0x48, 0x49, 0x4a, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f, \ + 0x50, 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57, \ + 0x58, 0x59, 0x5a, 0x5b, 0x5c, 0x5d, 0x5e, 0x5f, \ + 0x60, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47, \ + 0x48, 0x49, 0x4a, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f, \ + 0x50, 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57, \ + 0x58, 0x59, 0x5a, 0x7b, 0x7c, 0x7d, 0x7e, 0x7f, \ + 0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87, \ + 0x88, 0x89, 0x8a, 0x8b, 0x8c, 0x8d, 0x8e, 0x8f, \ + 0x90, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, \ + 0x98, 0x99, 0x9a, 0x9b, 0x9c, 0x9d, 0x9e, 0x9f, \ + 0xa0, 0xa1, 0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa7, \ + 0xa8, 0xa9, 0xaa, 0xab, 0xac, 0xad, 0xae, 0xaf, \ + 0xb0, 0xb1, 0xb2, 0xb3, 0xb4, 0xb5, 0xb6, 0xb7, \ + 0xb8, 0xb9, 0xba, 0xbb, 0xbc, 0xbd, 0xbe, 0xbf, \ + 0xc0, 0xc1, 0xc2, 0xc3, 0xc4, 0xc5, 0xc6, 0xc7, \ + 0xc8, 0xc9, 0xca, 0xcb, 0xcc, 0xcd, 0xce, 0xcf, \ + 0xd0, 0xd1, 0xd2, 0xd3, 0xd4, 0xd5, 0xd6, 0xd7, \ + 0xd8, 0xd9, 0xda, 0xdb, 0xdc, 0xdd, 0xde, 0xdf, \ + 0xe0, 0xe1, 0xe2, 0xe3, 0xe4, 0xe5, 0xe6, 0xe7, \ + 0xe8, 0xe9, 0xea, 0xeb, 0xec, 0xed, 0xee, 0xef, \ + 0xf0, 0xf1, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, \ + 0xf8, 0xf9, 0xfa, 0xfb, 0xfc, 0xfd, 0xfe, 0xff, \ +}) + +#ifdef USE_OBSOLETE_LINKER +/* some old linkers and some non-ELF platforms have issues with the weak + * attribute so we turn these arrays to literals there. + */ +#define ist_lc _IST_LC +#define ist_uc _IST_UC +#else +const unsigned char ist_lc[256] __attribute__((weak)) = _IST_LC; +const unsigned char ist_uc[256] __attribute__((weak)) = _IST_UC; +#endif + +/* This string definition will most often be used to represent a read-only + * string returned from a function, based on the starting point and its length + * in bytes. No storage is provided, only a pointer and a length. The types + * here are important as we only want to have 2 native machine words there so + * that on modern architectures the compiler is capable of efficiently + * returning a register pair without having to allocate stack room from the + * caller. This is done with -freg-struct which is often enabled by default. + */ +struct ist { + char *ptr; + size_t len; +}; + +/* makes a constant ist from a constant string, for use in array declarations */ +#define IST(str) { .ptr = str "", .len = (sizeof str "") - 1 } + +/* IST_NULL is equivalent to an `ist` with `.ptr = NULL` and `.len = 0` */ +#define IST_NULL ((const struct ist){ .ptr = 0, .len = 0 }) + +/* makes an ist from a regular zero terminated string. Null has length 0. + * Constants are detected and replaced with constant initializers. Other values + * are measured by hand without strlen() as it's much cheaper and inlinable on + * small strings. The construct is complex because we must never call + * __builtin_strlen() with an expression otherwise it involves a real + * measurement. + */ +#if __GNUC__ >= 4 +// gcc >= 4 detects constant propagation of str through __x and resolves the +// length of constant strings easily. +#define ist(str) ({ \ + char *__x = (void *)(str); \ + (struct ist){ \ + .ptr = __x, \ + .len = __builtin_constant_p(str) ? \ + ((void *)str == (void *)0) ? 0 : \ + __builtin_strlen(__x) : \ + ({ \ + size_t __l = 0; \ + if (__x) for (__l--; __x[++__l]; ) ; \ + __l; \ + }) \ + }; \ +}) +#else +// gcc < 4 can't do this, and the side effect is a warning each time a NULL is +// passed to ist() due to the check on __builtin_strlen(). It doesn't have the +// ability to know that this code is never called. +#define ist(str) ({ \ + char *__x = (void *)(str); \ + (struct ist){ \ + .ptr = __x, \ + .len = __builtin_constant_p(str) ? \ + ((void *)str == (void *)0) ? 0 : \ + __builtin_strlen(str) : \ + ({ \ + size_t __l = 0; \ + if (__x) for (__l--; __x[++__l]; ) ; \ + __l; \ + }) \ + }; \ +}) +#endif + +/* makes an ist struct from a string and a length */ +static inline struct ist ist2(const void *ptr, size_t len) +{ + return (struct ist){ .ptr = (char *)ptr, .len = len }; +} + +/* returns the result of `ist.ptr != NULL` */ +static inline int isttest(const struct ist ist) +{ + return ist.ptr != NULL; +} + +/* This function MODIFIES the string to add a zero AFTER the end, and returns + * the start pointer. The purpose is to use it on strings extracted by parsers + * from larger strings cut with delimiters that are not important and can be + * destroyed. It allows any such string to be used with regular string + * functions. It's also convenient to use with printf() to show data extracted + * from writable areas. The caller is obviously responsible for ensuring that + * the string is valid and that the first byte past the end is writable. If + * these conditions cannot be satisfied, use istpad() below instead. + */ +static inline char *ist0(struct ist ist) +{ + ist.ptr[ist.len] = 0; + return ist.ptr; +} + +/* returns the pointer of the string */ +static inline char *istptr(const struct ist ist) +{ + return ist.ptr; +} + +/* returns the length of the string */ +static inline size_t istlen(const struct ist ist) +{ + return ist.len; +} + +/* returns the pointer to the end the string */ +static inline char *istend(const struct ist ist) +{ + return (ist.ptr + ist.len); +} + +/* skips to next character in the string, always stops at the end */ +static inline struct ist istnext(const struct ist ist) +{ + struct ist ret = ist; + + if (ret.len) { + ret.len--; + ret.ptr++; + } + return ret; +} + +/* Returns the first character of the <ist> and advances the <ist> by 1. + * If the <ist> is empty the result is undefined. + */ +static inline char istshift(struct ist *ist) +{ + if (ist->len) { + char c = *ist->ptr; + *ist = istnext(*ist); + + return c; + } + + return 0; +} + +/* copies the contents from string <ist> to buffer <buf> and adds a trailing + * zero. The caller must ensure <buf> is large enough. + */ +static inline struct ist istpad(void *buf, const struct ist ist) +{ + struct ist ret = { .ptr = buf, .len = ist.len }; + + for (ret.len = 0; ret.len < ist.len; ret.len++) + ret.ptr[ret.len] = ist.ptr[ret.len]; + + ret.ptr[ret.len] = 0; + return ret; +} + +/* trims string <ist> to no more than <size> characters. The string is + * returned. + */ +static inline struct ist isttrim(const struct ist ist, size_t size) +{ + struct ist ret = ist; + + if (ret.len > size) + ret.len = size; + return ret; +} + +/* Sets the <len> of the <ist> to zero and returns the previous length. + * + * This function is meant to be used in functions that receive an ist containing + * the destination buffer and the buffer's size. The returned size must be stored + * to prevent an overflow of such a destination buffer. + * + * If you simply want to clear an ist and do not care about the previous length + * then you should use `isttrim(ist, 0)`. + * + * Example Usage (fill the complete buffer with 'x'): + * + * void my_func(struct ist* dst) + * { + * size_t dst_size = istclear(dst); + * size_t i; + * + * for (i = 0; i < dst_size; i++) + * *dst = __istappend(*dst, 'x'); + * } + */ +__attribute__((warn_unused_result)) +static inline size_t istclear(struct ist* ist) +{ + size_t len = ist->len; + + ist->len = 0; + + return len; +} + +/* trims string <ist> to no more than <size>-1 characters and ensures that a + * zero is placed after <ist.len> (possibly reduced by one) and before <size>, + * unless <size> is already zero. The string is returned. This is mostly aimed + * at building printable strings that need to be zero-terminated. + */ +static inline struct ist istzero(const struct ist ist, size_t size) +{ + struct ist ret = ist; + + if (!size) + ret.len = 0; + else { + if (ret.len > size - 1) + ret.len = size - 1; + ret.ptr[ret.len] = 0; + } + return ret; +} + +/* returns the ordinal difference between two strings : + * < 0 if ist1 < ist2 + * = 0 if ist1 == ist2 + * > 0 if ist1 > ist2 + */ +static inline int istdiff(const struct ist ist1, const struct ist ist2) +{ + struct ist l = ist1; + struct ist r = ist2; + + do { + if (!l.len--) + return -r.len; + if (!r.len--) + return 1; + } while (*l.ptr++ == *r.ptr++); + + return *(unsigned char *)(l.ptr - 1) - *(unsigned char *)(r.ptr - 1); +} + +/* returns non-zero if <ist1> starts like <ist2> (empty strings do match) */ +static inline int istmatch(const struct ist ist1, const struct ist ist2) +{ + struct ist l = ist1; + struct ist r = ist2; + + if (l.len < r.len) + return 0; + + while (r.len--) { + if (*l.ptr++ != *r.ptr++) + return 0; + } + return 1; +} + +/* returns non-zero if <ist1> starts like <ist2>, ignoring the case (empty strings do match) */ +static inline int istmatchi(const struct ist ist1, const struct ist ist2) +{ + struct ist l = ist1; + struct ist r = ist2; + + if (l.len < r.len) + return 0; + + while (r.len--) { + if (*l.ptr != *r.ptr && + ist_lc[(unsigned char)*l.ptr] != ist_lc[(unsigned char)*r.ptr]) + return 0; + + l.ptr++; + r.ptr++; + } + return 1; +} + +/* returns non-zero if <ist1> starts like <ist2> on the first <count> + * characters (empty strings do match). + */ +static inline int istnmatch(const struct ist ist1, const struct ist ist2, size_t count) +{ + struct ist l = ist1; + struct ist r = ist2; + + if (l.len > count) + l.len = count; + if (r.len > count) + r.len = count; + return istmatch(l, r); +} + +/* returns non-zero if <ist1> equals <ist2> (empty strings are equal) */ +static inline int isteq(const struct ist ist1, const struct ist ist2) +{ + struct ist l = ist1; + struct ist r = ist2; + + if (l.len != r.len) + return 0; + + while (l.len--) { + if (*l.ptr++ != *r.ptr++) + return 0; + } + return 1; +} + +/* returns non-zero if <ist1> equals <ist2>, ignoring the case (empty strings are equal) */ +static inline int isteqi(const struct ist ist1, const struct ist ist2) +{ + struct ist l = ist1; + struct ist r = ist2; + + if (l.len != r.len) + return 0; + + while (l.len--) { + if (*l.ptr != *r.ptr && + ist_lc[(unsigned char)*l.ptr] != ist_lc[(unsigned char)*r.ptr]) + return 0; + + l.ptr++; + r.ptr++; + } + return 1; +} + +/* returns non-zero if <ist1> equals <ist2> on the first <count> characters + * (empty strings are equal). + */ +static inline int istneq(const struct ist ist1, const struct ist ist2, size_t count) +{ + struct ist l = ist1; + struct ist r = ist2; + + if (l.len > count) + l.len = count; + if (r.len > count) + r.len = count; + return isteq(l, r); +} + +/* appends <src> after <dst>. The caller must ensure that the underlying buffer + * is large enough to fit the character. + */ +static inline struct ist __istappend(struct ist dst, const char src) +{ + dst.ptr[dst.len++] = src; + + return dst; +} + +/* copies <src> over <dst> for a maximum of <count> bytes. Returns the number + * of characters copied (src.len), or -1 if it does not fit. In all cases, the + * contents are copied prior to reporting an error, so that the destination + * at least contains a valid but truncated string. + */ +static inline ssize_t istcpy(struct ist *dst, const struct ist src, size_t count) +{ + dst->len = 0; + + if (count > src.len) + count = src.len; + + while (dst->len < count) { + dst->ptr[dst->len] = src.ptr[dst->len]; + dst->len++; + } + + if (dst->len == src.len) + return src.len; + + return -1; +} + +/* copies <src> over <dst> for a maximum of <count> bytes. Returns the number + * of characters copied, or -1 if it does not fit. A (possibly truncated) valid + * copy of <src> is always left into <dst>, and a trailing \0 is appended as + * long as <count> is not null, even if that results in reducing the string by + * one character. + */ +static inline ssize_t istscpy(struct ist *dst, const struct ist src, size_t count) +{ + dst->len = 0; + + if (!count) + goto fail; + + if (count > src.len) + count = src.len + 1; + + while (dst->len < count - 1) { + dst->ptr[dst->len] = src.ptr[dst->len]; + dst->len++; + } + + dst->ptr[dst->len] = 0; + if (dst->len == src.len) + return src.len; + fail: + return -1; +} + +/* appends <src> after <dst> for a maximum of <count> total bytes in <dst> after + * the copy. <dst> is assumed to be <count> or less before the call. The new + * string's length is returned, or -1 if a truncation happened. In all cases, + * the contents are copied prior to reporting an error, so that the destination + * at least contains a valid but truncated string. + */ +static inline ssize_t istcat(struct ist *dst, const struct ist src, size_t count) +{ + const char *s = src.ptr; + + while (dst->len < count && s != src.ptr + src.len) + dst->ptr[dst->len++] = *s++; + + if (s == src.ptr + src.len) + return dst->len; + + return -1; +} + +/* appends <src> after <dst> for a maximum of <count> total bytes in <dst> after + * the copy. <dst> is assumed to be <count> or less before the call. The new + * string's length is returned, or -1 if a truncation happened. In all cases, + * the contents are copied prior to reporting an error, so that the destination + * at least contains a valid but truncated string. + */ +static inline ssize_t istscat(struct ist *dst, const struct ist src, size_t count) +{ + const char *s = src.ptr; + + if (!count) + goto fail; + + while (dst->len < count - 1 && s != src.ptr + src.len) { + dst->ptr[dst->len++] = *s++; + } + + dst->ptr[dst->len] = 0; + if (s == src.ptr + src.len) + return dst->len; + fail: + return -1; +} + +/* copies the entire <src> over <dst>, which must be allocated large enough to + * hold the whole contents. No trailing zero is appended, this is mainly used + * for protocol processing where the frame length has already been checked. An + * ist made of the output and its length are returned. The destination is not + * touched if src.len is null. + */ +static inline struct ist ist2bin(char *dst, const struct ist src) +{ + size_t ofs = 0; + + /* discourage the compiler from trying to optimize for large strings, + * but tell it that most of our strings are not empty. + */ + if (__builtin_expect(ofs < src.len, 1)) { + do { + dst[ofs] = src.ptr[ofs]; + ofs++; + } while (__builtin_expect(ofs < src.len, 0)); + } + return ist2(dst, ofs); +} + +/* copies the entire <src> over <dst>, which must be allocated large enough to + * hold the whole contents as well as a trailing zero which is always appended. + * This is mainly used for protocol conversions where the frame length has + * already been checked. An ist made of the output and its length (not counting + * the trailing zero) are returned. + */ +static inline struct ist ist2str(char *dst, const struct ist src) +{ + size_t ofs = 0; + + /* discourage the compiler from trying to optimize for large strings, + * but tell it that most of our strings are not empty. + */ + if (__builtin_expect(ofs < src.len, 1)) { + do { + dst[ofs] = src.ptr[ofs]; + ofs++; + } while (__builtin_expect(ofs < src.len, 0)); + } + dst[ofs] = 0; + return ist2(dst, ofs); +} + +/* makes a lower case copy of the entire <src> into <dst>, which must have been + * allocated large enough to hold the whole contents. No trailing zero is + * appended, this is mainly used for protocol processing where the frame length + * has already been checked. An ist made of the output and its length are + * returned. The destination is not touched if src.len is null. + */ +static inline struct ist ist2bin_lc(char *dst, const struct ist src) +{ + size_t ofs = 0; + + /* discourage the compiler from trying to optimize for large strings, + * but tell it that most of our strings are not empty. + */ + if (__builtin_expect(ofs < src.len, 1)) { + do { + dst[ofs] = ist_lc[(unsigned char)src.ptr[ofs]]; + ofs++; + } while (__builtin_expect(ofs < src.len, 0)); + } + return ist2(dst, ofs); +} + +/* makes a lower case copy of the entire <src> into <dst>, which must have been + * allocated large enough to hold the whole contents as well as a trailing zero + * which is always appended. This is mainly used for protocol conversions where + * the frame length has already been checked. An ist made of the output and its + * length (not counting the trailing zero) are returned. + */ +static inline struct ist ist2str_lc(char *dst, const struct ist src) +{ + size_t ofs = 0; + + /* discourage the compiler from trying to optimize for large strings, + * but tell it that most of our strings are not empty. + */ + if (__builtin_expect(ofs < src.len, 1)) { + do { + dst[ofs] = ist_lc[(unsigned char)src.ptr[ofs]]; + ofs++; + } while (__builtin_expect(ofs < src.len, 0)); + } + dst[ofs] = 0; + return ist2(dst, ofs); +} + +/* makes an upper case copy of the entire <src> into <dst>, which must have + * been allocated large enough to hold the whole contents. No trailing zero is + * appended, this is mainly used for protocol processing where the frame length + * has already been checked. An ist made of the output and its length are + * returned. The destination is not touched if src.len is null. + */ +static inline struct ist ist2bin_uc(char *dst, const struct ist src) +{ + size_t ofs = 0; + + /* discourage the compiler from trying to optimize for large strings, + * but tell it that most of our strings are not empty. + */ + if (__builtin_expect(ofs < src.len, 1)) { + do { + dst[ofs] = ist_uc[(unsigned char)src.ptr[ofs]]; + ofs++; + } while (__builtin_expect(ofs < src.len, 0)); + } + return ist2(dst, ofs); +} + +/* makes an upper case copy of the entire <src> into <dst>, which must have been + * allocated large enough to hold the whole contents as well as a trailing zero + * which is always appended. This is mainly used for protocol conversions where + * the frame length has already been checked. An ist made of the output and its + * length (not counting the trailing zero) are returned. + */ +static inline struct ist ist2str_uc(char *dst, const struct ist src) +{ + size_t ofs = 0; + + /* discourage the compiler from trying to optimize for large strings, + * but tell it that most of our strings are not empty. + */ + if (__builtin_expect(ofs < src.len, 1)) { + do { + dst[ofs] = ist_uc[(unsigned char)src.ptr[ofs]]; + ofs++; + } while (__builtin_expect(ofs < src.len, 0)); + } + dst[ofs] = 0; + return ist2(dst, ofs); +} + +/* looks for first occurrence of character <chr> in string <ist>. Returns the + * pointer if found, or NULL if not found. + */ +static inline char *istchr(const struct ist ist, char chr) +{ + char *s = ist.ptr; + + do { + if (s >= ist.ptr + ist.len) + return NULL; + } while (*s++ != chr); + return s - 1; +} + +/* Returns a pointer to the first control character found in <ist>, or NULL if + * none is present. A control character is defined as a byte whose value is + * between 0x00 and 0x1F included. The function is optimized for strings having + * no CTL chars by processing up to sizeof(long) bytes at once on architectures + * supporting efficient unaligned accesses. Despite this it is not very fast + * (~0.43 byte/cycle) and should mostly be used on low match probability when + * it can save a call to a much slower function. + */ +static inline const char *ist_find_ctl(const struct ist ist) +{ + const union { unsigned long v; } __attribute__((packed)) *u; + const char *curr = (void *)ist.ptr - sizeof(long); + const char *last = curr + ist.len; + unsigned long l1, l2; + + do { + curr += sizeof(long); + if (curr > last) + break; + u = (void *)curr; + /* subtract 0x202020...20 to the value to generate a carry in + * the lower byte if the byte contains a lower value. If we + * generate a bit 7 that was not there, it means the byte was + * within 0x00..0x1F. + */ + l2 = u->v; + l1 = ~l2 & ((~0UL / 255) * 0x80); /* 0x808080...80 */ + l2 -= (~0UL / 255) * 0x20; /* 0x202020...20 */ + } while ((l1 & l2) == 0); + + last += sizeof(long); + if (__builtin_expect(curr < last, 0)) { + do { + if ((unsigned char)*curr < 0x20) + return curr; + curr++; + } while (curr < last); + } + return NULL; +} + +/* looks for first occurrence of character <chr> in string <ist> and returns + * the tail of the string starting with this character, or (ist.end,0) if not + * found. + */ +static inline struct ist istfind(const struct ist ist, char chr) +{ + struct ist ret = ist; + + while (ret.len--) { + if (*ret.ptr++ == chr) + return ist2(ret.ptr - 1, ret.len + 1); + } + return ist2(ret.ptr, 0); +} + +/* looks for first occurrence of character different from <chr> in string <ist> + * and returns the tail of the string starting at this character, or (ist_end,0) + * if not found. + */ +static inline struct ist istskip(const struct ist ist, char chr) +{ + struct ist ret = ist; + + while (ret.len--) { + if (*ret.ptr++ != chr) + return ist2(ret.ptr - 1, ret.len + 1); + } + return ist2(ret.ptr, 0); +} + +/* looks for first occurrence of string <pat> in string <ist> and returns the + * tail of the string starting at this position, or (NULL,0) if not found. The + * empty pattern is found everywhere. + */ +static inline struct ist istist(const struct ist ist, const struct ist pat) +{ + struct ist ret = ist; + size_t pos; + + if (!pat.len) + return ret; + + while (1) { + loop: + ret = istfind(ret, *pat.ptr); + if (ret.len < pat.len) + break; + + /* ret.len >= 1, pat.len >= 1 and *ret.ptr == *pat.ptr */ + + ret = istnext(ret); + for (pos = 0; pos < pat.len - 1; ) { + ++pos; + if (ret.ptr[pos - 1] != pat.ptr[pos]) + goto loop; + } + return ist2(ret.ptr - 1, ret.len + 1); + } + return IST_NULL; +} + +/* + * looks for the first occurrence of <chr> in string <ist> and returns a shorter + * ist if char is found. + */ +static inline struct ist iststop(const struct ist ist, char chr) +{ + size_t len = 0; + + while (len++ < ist.len && ist.ptr[len - 1] != chr) + ; + return ist2(ist.ptr, len - 1); +} + +/* + * advance <.ptr> by <nb> characters. + * If <ist> is too short, (ist.end,0) is returned. + */ +static inline struct ist istadv(const struct ist ist, const size_t nb) +{ + if (ist.len < nb) + return ist2(ist.ptr + ist.len, 0); + return ist2(ist.ptr + nb, ist.len - nb); +} + +/* Splits the given <ist> at the given character. The returned ist is + * equivalent to iststop(ist, delim). The passed <ist> will contain the + * remainder of the string, not including the delimiter. In other words + * it will be advanced by the length of the returned string plus 1. + */ +static inline struct ist istsplit(struct ist *ist, char delim) +{ + const struct ist result = iststop(*ist, delim); + + *ist = istadv(*ist, result.len + 1); + + return result; +} + +/* + * compare 2 ists and return non-zero if they are the same + */ +static inline int istissame(const struct ist ist1, const struct ist ist2) +{ + return ((ist1.ptr == ist2.ptr) && (ist1.len == ist2.len)); +} + +#ifndef IST_FREESTANDING +/* This function allocates <size> bytes and returns an `ist` pointing to + * the allocated area with size `0`. + * + * If this function fails to allocate memory the return value is equivalent + * to IST_NULL. + */ +static inline struct ist istalloc(const size_t size) +{ + /* Note: do not use ist2 here, as it triggers a gcc11 warning. + * €˜<unknown>€™ may be used uninitialized [-Werror=maybe-uninitialized] + * + * This warning is reported because the uninitialized memory block + * allocated by malloc should not be passed to a const argument as in + * ist2. + * See https://gcc.gnu.org/onlinedocs/gcc-11.1.0/gcc/Warning-Options.html#index-Wmaybe-uninitialized + */ + return (struct ist){ .ptr = malloc(size), .len = 0 }; +} + +/* This function performs the equivalent of free() on the given <ist>. + * + * After this function returns the value of the given <ist> will be + * modified to be equivalent to IST_NULL. + */ +static inline void istfree(struct ist *ist) +{ + free(ist->ptr); + *ist = IST_NULL; +} + +/* This function performs the equivalent of strdup() on the given <src>. + * + * If this function fails to allocate memory the return value is equivalent + * to IST_NULL. + */ +static inline struct ist istdup(const struct ist src) +{ + const size_t src_size = src.len; + + /* Allocate at least 1 byte to allow duplicating an empty string with + * malloc implementations that return NULL for a 0-size allocation. + */ + struct ist dst = istalloc(src_size ? src_size : 1); + + if (isttest(dst)) { + istcpy(&dst, src, src_size); + } + + return dst; +} +#endif + +#endif |