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Diffstat (limited to 'mysql/m_string.h')
| -rw-r--r-- | mysql/m_string.h | 341 |
1 files changed, 341 insertions, 0 deletions
diff --git a/mysql/m_string.h b/mysql/m_string.h new file mode 100644 index 0000000..ee9f869 --- /dev/null +++ b/mysql/m_string.h @@ -0,0 +1,341 @@ +/* + Copyright (c) 2000, 2015, Oracle and/or its affiliates. All rights reserved. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; version 2 of the License. + + This program 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 General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software + Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */ + +#ifndef _m_string_h +#define _m_string_h + +#include "my_global.h" /* HAVE_* */ + +#include <string.h> + +#define bfill please_use_memset_rather_than_bfill +#define bzero please_use_memset_rather_than_bzero +#define bmove please_use_memmove_rather_than_bmove +#define strmov please_use_my_stpcpy_or_my_stpmov_rather_than_strmov +#define strnmov please_use_my_stpncpy_or_my_stpnmov_rather_than_strnmov + +#include "mysql/service_my_snprintf.h" + +#if defined(__cplusplus) +extern "C" { +#endif + +/* + my_str_malloc(), my_str_realloc() and my_str_free() are assigned to + implementations in strings/alloc.c, but can be overridden in + the calling program. + */ +extern void *(*my_str_malloc)(size_t); +extern void *(*my_str_realloc)(void *, size_t); +extern void (*my_str_free)(void *); + +/* Declared in int2str() */ +extern char _dig_vec_upper[]; +extern char _dig_vec_lower[]; + + /* Prototypes for string functions */ + +extern void bchange(uchar *dst,size_t old_len,const uchar *src, + size_t new_len,size_t tot_len); +extern void strappend(char *s,size_t len,pchar fill); +extern char *strend(const char *s); +extern char *strcend(const char *, pchar); +extern char *strfill(char * s,size_t len,pchar fill); +extern char *strmake(char *dst,const char *src,size_t length); + +extern char *my_stpmov(char *dst,const char *src); +extern char *my_stpnmov(char *dst, const char *src, size_t n); +extern char *strcont(const char *src, const char *set); +extern char *strxmov(char *dst, const char *src, ...); +extern char *strxnmov(char *dst, size_t len, const char *src, ...); + +/** + Copy a string from src to dst until (and including) terminating null byte. + + @param dst Destination + @param src Source + + @note src and dst cannot overlap. + Use my_stpmov() if src and dst overlaps. + + @note Unsafe, consider using my_stpnpy() instead. + + @return pointer to terminating null byte. +*/ +static inline char *my_stpcpy(char *dst, const char *src) +{ +#if defined(HAVE_BUILTIN_STPCPY) + return __builtin_stpcpy(dst, src); +#elif defined(HAVE_STPCPY) + return stpcpy(dst, src); +#else + /* Fallback to implementation supporting overlap. */ + return my_stpmov(dst, src); +#endif +} + +/** + Copy fixed-size string from src to dst. + + @param dst Destination + @param src Source + @param n Maximum number of characters to copy. + + @note src and dst cannot overlap + Use my_stpnmov() if src and dst overlaps. + + @return pointer to terminating null byte. +*/ +static inline char *my_stpncpy(char *dst, const char *src, size_t n) +{ +#if defined(HAVE_STPNCPY) + return stpncpy(dst, src, n); +#else + /* Fallback to implementation supporting overlap. */ + return my_stpnmov(dst, src, n); +#endif +} + +static inline longlong my_strtoll(const char *nptr, char **endptr, int base) +{ +#if defined _WIN32 + return _strtoi64(nptr, endptr, base); +#else + return strtoll(nptr, endptr, base); +#endif +} + +static inline ulonglong my_strtoull(const char *nptr, char **endptr, int base) +{ +#if defined _WIN32 + return _strtoui64(nptr, endptr, base); +#else + return strtoull(nptr, endptr, base); +#endif +} + +static inline char *my_strtok_r(char *str, const char *delim, char **saveptr) +{ +#if defined _WIN32 + return strtok_s(str, delim, saveptr); +#else + return strtok_r(str, delim, saveptr); +#endif +} + +/* native_ rather than my_ since my_strcasecmp already exists */ +static inline int native_strcasecmp(const char *s1, const char *s2) +{ +#if defined _WIN32 + return _stricmp(s1, s2); +#else + return strcasecmp(s1, s2); +#endif +} + +/* native_ rather than my_ for consistency with native_strcasecmp */ +static inline int native_strncasecmp(const char *s1, const char *s2, size_t n) +{ +#if defined _WIN32 + return _strnicmp(s1, s2, n); +#else + return strncasecmp(s1, s2, n); +#endif +} + +/* Prototypes of normal stringfunctions (with may ours) */ +#ifndef HAVE_STRNLEN +extern size_t strnlen(const char *s, size_t n); +#endif + +extern int is_prefix(const char *, const char *); + +/* Conversion routines */ +typedef enum { + MY_GCVT_ARG_FLOAT, + MY_GCVT_ARG_DOUBLE +} my_gcvt_arg_type; + +double my_strtod(const char *str, char **end, int *error); +double my_atof(const char *nptr); +size_t my_fcvt(double x, int precision, char *to, my_bool *error); +size_t my_gcvt(double x, my_gcvt_arg_type type, int width, char *to, + my_bool *error); + +#define NOT_FIXED_DEC 31 + +/* + The longest string my_fcvt can return is 311 + "precision" bytes. + Here we assume that we never cal my_fcvt() with precision >= NOT_FIXED_DEC + (+ 1 byte for the terminating '\0'). +*/ +#define FLOATING_POINT_BUFFER (311 + NOT_FIXED_DEC) + +/* + We want to use the 'e' format in some cases even if we have enough space + for the 'f' one just to mimic sprintf("%.15g") behavior for large integers, + and to improve it for numbers < 10^(-4). + That is, for |x| < 1 we require |x| >= 10^(-15), and for |x| > 1 we require + it to be integer and be <= 10^DBL_DIG for the 'f' format to be used. + We don't lose precision, but make cases like "1e200" or "0.00001" look nicer. +*/ +#define MAX_DECPT_FOR_F_FORMAT DBL_DIG + +/* + The maximum possible field width for my_gcvt() conversion. + (DBL_DIG + 2) significant digits + sign + "." + ("e-NNN" or + MAX_DECPT_FOR_F_FORMAT zeros for cases when |x|<1 and the 'f' format is used). +*/ +#define MY_GCVT_MAX_FIELD_WIDTH (DBL_DIG + 4 + MY_MAX(5, MAX_DECPT_FOR_F_FORMAT)) \ + +extern char *llstr(longlong value,char *buff); +extern char *ullstr(longlong value,char *buff); + +extern char *int2str(long val, char *dst, int radix, int upcase); +extern char *int10_to_str(long val,char *dst,int radix); +extern char *str2int(const char *src,int radix,long lower,long upper, + long *val); +longlong my_strtoll10(const char *nptr, char **endptr, int *error); +#if SIZEOF_LONG == SIZEOF_LONG_LONG +#define ll2str(A,B,C,D) int2str((A),(B),(C),(D)) +#define longlong10_to_str(A,B,C) int10_to_str((A),(B),(C)) +#undef strtoll +#define strtoll(A,B,C) strtol((A),(B),(C)) +#define strtoull(A,B,C) strtoul((A),(B),(C)) +#else +extern char *ll2str(longlong val,char *dst,int radix, int upcase); +extern char *longlong10_to_str(longlong val,char *dst,int radix); +#endif +#define longlong2str(A,B,C) ll2str((A),(B),(C),1) + +#if defined(__cplusplus) +} +#endif + +/* + LEX_STRING -- a pair of a C-string and its length. + (it's part of the plugin API as a MYSQL_LEX_STRING) + Ditto LEX_CSTRING/MYSQL_LEX_CSTRING. +*/ + +#include <mysql/mysql_lex_string.h> +typedef struct st_mysql_lex_string LEX_STRING; +typedef struct st_mysql_const_lex_string LEX_CSTRING; + +#define STRING_WITH_LEN(X) (X), ((sizeof(X) - 1)) +#define USTRING_WITH_LEN(X) ((uchar*) X), ((sizeof(X) - 1)) +#define C_STRING_WITH_LEN(X) ((char *) (X)), ((sizeof(X) - 1)) + + +/** + Skip trailing space. + + On most systems reading memory in larger chunks (ideally equal to the size of + the chinks that the machine physically reads from memory) causes fewer memory + access loops and hence increased performance. + This is why the 'int' type is used : it's closest to that (according to how + it's defined in C). + So when we determine the amount of whitespace at the end of a string we do + the following : + 1. We divide the string into 3 zones : + a) from the start of the string (__start) to the first multiple + of sizeof(int) (__start_words) + b) from the end of the string (__end) to the last multiple of sizeof(int) + (__end_words) + c) a zone that is aligned to sizeof(int) and can be safely accessed + through an int * + 2. We start comparing backwards from (c) char-by-char. If all we find is + space then we continue + 3. If there are elements in zone (b) we compare them as unsigned ints to a + int mask (SPACE_INT) consisting of all spaces + 4. Finally we compare the remaining part (a) of the string char by char. + This covers for the last non-space unsigned int from 3. (if any) + + This algorithm works well for relatively larger strings, but it will slow + the things down for smaller strings (because of the additional calculations + and checks compared to the naive method). Thus the barrier of length 20 + is added. + + @param ptr pointer to the input string + @param len the length of the string + @return the last non-space character +*/ +#if defined(__sparc) || defined(__sparcv9) +static inline const uchar *skip_trailing_space(const uchar *ptr,size_t len) +{ + /* SPACE_INT is a word that contains only spaces */ +#if SIZEOF_INT == 4 + const unsigned SPACE_INT= 0x20202020U; +#elif SIZEOF_INT == 8 + const unsigned SPACE_INT= 0x2020202020202020ULL; +#else +#error define the appropriate constant for a word full of spaces +#endif + + const uchar *end= ptr + len; + + if (len > 20) + { + const uchar *end_words= (const uchar *)(intptr) + (((ulonglong)(intptr)end) / SIZEOF_INT * SIZEOF_INT); + const uchar *start_words= (const uchar *)(intptr) + ((((ulonglong)(intptr)ptr) + SIZEOF_INT - 1) / SIZEOF_INT * SIZEOF_INT); + + DBUG_ASSERT(end_words > ptr); + while (end > end_words && end[-1] == 0x20) + end--; + if (end[-1] == 0x20 && start_words < end_words) + while (end > start_words && ((unsigned *)end)[-1] == SPACE_INT) + end -= SIZEOF_INT; + } + while (end > ptr && end[-1] == 0x20) + end--; + return (end); +} +#else +/* + Reads 8 bytes at a time, ignoring alignment. + We use uint8korr, which is fast (it simply reads a *ulonglong) + on all platforms, except sparc. +*/ +static inline const uchar *skip_trailing_space(const uchar *ptr, size_t len) +{ + const uchar *end= ptr + len; + while (end - ptr >= 8) + { + if (uint8korr(end-8) != 0x2020202020202020ULL) + break; + end-= 8; + } + while (end > ptr && end[-1] == 0x20) + end--; + return (end); +} +#endif + +static inline void lex_string_set(LEX_STRING *lex_str, const char *c_str) +{ + lex_str->str= (char *) c_str; + lex_str->length= strlen(c_str); +} + +static inline void lex_cstring_set(LEX_CSTRING *lex_str, const char *c_str) +{ + lex_str->str= c_str; + lex_str->length= strlen(c_str); +} + +#endif |