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27 // 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
28 
29 #ifndef _m_string_h
30 #define _m_string_h
31 
32 #include "my_global.h"                          /* HAVE_* */
33 
34 #include <string.h>
35 
36 #define bfill please_use_memset_rather_than_bfill
37 #define bzero please_use_memset_rather_than_bzero
38 #define bmove please_use_memmove_rather_than_bmove
39 #define strmov please_use_my_stpcpy_or_my_stpmov_rather_than_strmov
40 #define strnmov please_use_my_stpncpy_or_my_stpnmov_rather_than_strnmov
41 
42 #include "mysql/service_my_snprintf.h"
43 
44 #if defined(__cplusplus)
45 extern "C" {
46 #endif
47 
48 /*
49   my_str_malloc(), my_str_realloc() and my_str_free() are assigned to
50   implementations in strings/alloc.c, but can be overridden in
51   the calling program.
52  */
53 extern void *(*my_str_malloc)(size_t);
54 extern void *(*my_str_realloc)(void *, size_t);
55 extern void (*my_str_free)(void *);
56 
57 /* Declared in int2str() */
58 extern char _dig_vec_upper[];
59 extern char _dig_vec_lower[];
60 
61 	/* Prototypes for string functions */
62 
63 extern	void bchange(uchar *dst,size_t old_len,const uchar *src,
64 		     size_t new_len,size_t tot_len);
65 extern	void strappend(char *s,size_t len,pchar fill);
66 extern	char *strend(const char *s);
67 extern  char *strcend(const char *, pchar);
68 extern	char *strfill(char * s,size_t len,pchar fill);
69 extern	char *strmake(char *dst,const char *src,size_t length);
70 
71 extern	char *my_stpmov(char *dst,const char *src);
72 extern	char *my_stpnmov(char *dst, const char *src, size_t n);
73 extern	char *strcont(const char *src, const char *set);
74 extern	char *strxmov(char *dst, const char *src, ...);
75 extern	char *strxnmov(char *dst, size_t len, const char *src, ...);
76 
77 /**
78    Copy a string from src to dst until (and including) terminating null byte.
79 
80    @param dst   Destination
81    @param src   Source
82 
83    @note src and dst cannot overlap.
84          Use my_stpmov() if src and dst overlaps.
85 
86    @note Unsafe, consider using my_stpnpy() instead.
87 
88    @return pointer to terminating null byte.
89 */
my_stpcpy(char * dst,const char * src)90 static inline char *my_stpcpy(char *dst, const char *src)
91 {
92 #if defined(HAVE_BUILTIN_STPCPY)
93   return __builtin_stpcpy(dst, src);
94 #elif defined(HAVE_STPCPY)
95   return stpcpy(dst, src);
96 #else
97   /* Fallback to implementation supporting overlap. */
98   return my_stpmov(dst, src);
99 #endif
100 }
101 
102 /**
103    Copy fixed-size string from src to dst.
104 
105    @param dst   Destination
106    @param src   Source
107    @param n     Maximum number of characters to copy.
108 
109    @note src and dst cannot overlap
110          Use my_stpnmov() if src and dst overlaps.
111 
112    @return pointer to terminating null byte.
113 */
my_stpncpy(char * dst,const char * src,size_t n)114 static inline char *my_stpncpy(char *dst, const char *src, size_t n)
115 {
116 #if defined(HAVE_STPNCPY)
117   return stpncpy(dst, src, n);
118 #else
119   /* Fallback to implementation supporting overlap. */
120   return my_stpnmov(dst, src, n);
121 #endif
122 }
123 
my_strtoll(const char * nptr,char ** endptr,int base)124 static inline longlong my_strtoll(const char *nptr, char **endptr, int base)
125 {
126 #if defined _WIN32
127   return _strtoi64(nptr, endptr, base);
128 #else
129   return strtoll(nptr, endptr, base);
130 #endif
131 }
132 
my_strtoull(const char * nptr,char ** endptr,int base)133 static inline ulonglong my_strtoull(const char *nptr, char **endptr, int base)
134 {
135 #if defined _WIN32
136   return _strtoui64(nptr, endptr, base);
137 #else
138   return strtoull(nptr, endptr, base);
139 #endif
140 }
141 
my_strtok_r(char * str,const char * delim,char ** saveptr)142 static inline char *my_strtok_r(char *str, const char *delim, char **saveptr)
143 {
144 #if defined _WIN32
145   return strtok_s(str, delim, saveptr);
146 #else
147   return strtok_r(str, delim, saveptr);
148 #endif
149 }
150 
151 /* native_ rather than my_ since my_strcasecmp already exists */
native_strcasecmp(const char * s1,const char * s2)152 static inline int native_strcasecmp(const char *s1, const char *s2)
153 {
154 #if defined _WIN32
155   return _stricmp(s1, s2);
156 #else
157   return strcasecmp(s1, s2);
158 #endif
159 }
160 
161 /* native_ rather than my_ for consistency with native_strcasecmp */
native_strncasecmp(const char * s1,const char * s2,size_t n)162 static inline int native_strncasecmp(const char *s1, const char *s2, size_t n)
163 {
164 #if defined _WIN32
165   return _strnicmp(s1, s2, n);
166 #else
167   return strncasecmp(s1, s2, n);
168 #endif
169 }
170 
171 /* Prototypes of normal stringfunctions (with may ours) */
172 #ifndef HAVE_STRNLEN
173 extern size_t strnlen(const char *s, size_t n);
174 #endif
175 
176 extern int is_prefix(const char *, const char *);
177 
178 /* Conversion routines */
179 typedef enum {
180   MY_GCVT_ARG_FLOAT,
181   MY_GCVT_ARG_DOUBLE
182 } my_gcvt_arg_type;
183 
184 double my_strtod(const char *str, char **end, int *error);
185 double my_atof(const char *nptr);
186 size_t my_fcvt(double x, int precision, char *to, my_bool *error);
187 size_t my_gcvt(double x, my_gcvt_arg_type type, int width, char *to,
188                my_bool *error);
189 
190 #define NOT_FIXED_DEC 31
191 
192 /*
193   The longest string my_fcvt can return is 311 + "precision" bytes.
194   Here we assume that we never cal my_fcvt() with precision >= NOT_FIXED_DEC
195   (+ 1 byte for the terminating '\0').
196 */
197 #define FLOATING_POINT_BUFFER (311 + NOT_FIXED_DEC)
198 
199 /*
200   We want to use the 'e' format in some cases even if we have enough space
201   for the 'f' one just to mimic sprintf("%.15g") behavior for large integers,
202   and to improve it for numbers < 10^(-4).
203   That is, for |x| < 1 we require |x| >= 10^(-15), and for |x| > 1 we require
204   it to be integer and be <= 10^DBL_DIG for the 'f' format to be used.
205   We don't lose precision, but make cases like "1e200" or "0.00001" look nicer.
206 */
207 #define MAX_DECPT_FOR_F_FORMAT DBL_DIG
208 
209 /*
210   The maximum possible field width for my_gcvt() conversion.
211   (DBL_DIG + 2) significant digits + sign + "." + ("e-NNN" or
212   MAX_DECPT_FOR_F_FORMAT zeros for cases when |x|<1 and the 'f' format is used).
213 */
214 #define MY_GCVT_MAX_FIELD_WIDTH (DBL_DIG + 4 + MY_MAX(5, MAX_DECPT_FOR_F_FORMAT)) \
215 
216 extern char *llstr(longlong value,char *buff);
217 extern char *ullstr(longlong value,char *buff);
218 
219 extern char *int2str(long val, char *dst, int radix, int upcase);
220 extern char *int10_to_str(long val,char *dst,int radix);
221 extern char *str2int(const char *src,int radix,long lower,long upper,
222 			 long *val);
223 longlong my_strtoll10(const char *nptr, char **endptr, int *error);
224 #if SIZEOF_LONG == SIZEOF_LONG_LONG
225 #define longlong10_to_str(A,B,C) int10_to_str((A),(B),(C))
226 #undef strtoll
227 #define strtoll(A,B,C) strtol((A),(B),(C))
228 #define strtoull(A,B,C) strtoul((A),(B),(C))
229 #else
230 extern char *longlong10_to_str(longlong val,char *dst,int radix);
231 #endif
232 
233 #if defined(__cplusplus)
234 }
235 #endif
236 
237 /*
238   LEX_STRING -- a pair of a C-string and its length.
239   (it's part of the plugin API as a MYSQL_LEX_STRING)
240   Ditto LEX_CSTRING/MYSQL_LEX_CSTRING.
241 */
242 
243 #include <mysql/mysql_lex_string.h>
244 typedef struct st_mysql_lex_string LEX_STRING;
245 typedef struct st_mysql_const_lex_string LEX_CSTRING;
246 
247 #define STRING_WITH_LEN(X) (X), ((sizeof(X) - 1))
248 #define USTRING_WITH_LEN(X) ((uchar*) X), ((sizeof(X) - 1))
249 #define C_STRING_WITH_LEN(X) ((char *) (X)), ((sizeof(X) - 1))
250 
251 
252 /**
253   Skip trailing space.
254 
255   On most systems reading memory in larger chunks (ideally equal to the size of
256   the chinks that the machine physically reads from memory) causes fewer memory
257   access loops and hence increased performance.
258   This is why the 'int' type is used : it's closest to that (according to how
259   it's defined in C).
260   So when we determine the amount of whitespace at the end of a string we do
261   the following :
262     1. We divide the string into 3 zones :
263       a) from the start of the string (__start) to the first multiple
264         of sizeof(int)  (__start_words)
265       b) from the end of the string (__end) to the last multiple of sizeof(int)
266         (__end_words)
267       c) a zone that is aligned to sizeof(int) and can be safely accessed
268         through an int *
269     2. We start comparing backwards from (c) char-by-char. If all we find is
270        space then we continue
271     3. If there are elements in zone (b) we compare them as unsigned ints to a
272        int mask (SPACE_INT) consisting of all spaces
273     4. Finally we compare the remaining part (a) of the string char by char.
274        This covers for the last non-space unsigned int from 3. (if any)
275 
276    This algorithm works well for relatively larger strings, but it will slow
277    the things down for smaller strings (because of the additional calculations
278    and checks compared to the naive method). Thus the barrier of length 20
279    is added.
280 
281    @param     ptr   pointer to the input string
282    @param     len   the length of the string
283    @return          the last non-space character
284 */
285 #if defined(__sparc) || defined(__sparcv9)
skip_trailing_space(const uchar * ptr,size_t len)286 static inline const uchar *skip_trailing_space(const uchar *ptr,size_t len)
287 {
288   /* SPACE_INT is a word that contains only spaces */
289 #if SIZEOF_INT == 4
290   const unsigned SPACE_INT= 0x20202020U;
291 #elif SIZEOF_INT == 8
292   const unsigned SPACE_INT= 0x2020202020202020ULL;
293 #else
294 #error define the appropriate constant for a word full of spaces
295 #endif
296 
297   const uchar *end= ptr + len;
298 
299   if (len > 20)
300   {
301     const uchar *end_words= (const uchar *)(intptr)
302       (((ulonglong)(intptr)end) / SIZEOF_INT * SIZEOF_INT);
303     const uchar *start_words= (const uchar *)(intptr)
304        ((((ulonglong)(intptr)ptr) + SIZEOF_INT - 1) / SIZEOF_INT * SIZEOF_INT);
305 
306     DBUG_ASSERT(end_words > ptr);
307     while (end > end_words && end[-1] == 0x20)
308       end--;
309     if (end[-1] == 0x20 && start_words < end_words)
310       while (end > start_words && ((unsigned *)end)[-1] == SPACE_INT)
311         end -= SIZEOF_INT;
312   }
313   while (end > ptr && end[-1] == 0x20)
314     end--;
315   return (end);
316 }
317 #else
318 /*
319   Reads 8 bytes at a time, ignoring alignment.
320   We use uint8korr, which is fast (it simply reads a *ulonglong)
321   on all platforms, except sparc.
322 */
skip_trailing_space(const uchar * ptr,size_t len)323 static inline const uchar *skip_trailing_space(const uchar *ptr, size_t len)
324 {
325   const uchar *end= ptr + len;
326   while (end - ptr >= 8)
327   {
328     if (uint8korr(end-8) != 0x2020202020202020ULL)
329       break;
330     end-= 8;
331   }
332   while (end > ptr && end[-1] == 0x20)
333     end--;
334   return (end);
335 }
336 #endif
337 
lex_string_set(LEX_STRING * lex_str,const char * c_str)338 static inline void lex_string_set(LEX_STRING *lex_str, const char *c_str)
339 {
340   lex_str->str= (char *) c_str;
341   lex_str->length= strlen(c_str);
342 }
343 
lex_cstring_set(LEX_CSTRING * lex_str,const char * c_str)344 static inline void lex_cstring_set(LEX_CSTRING *lex_str, const char *c_str)
345 {
346   lex_str->str= c_str;
347   lex_str->length= strlen(c_str);
348 }
349 
350 #endif
351