diff options
Diffstat (limited to 'strings')
| -rw-r--r-- | strings/CMakeLists.txt | 2 | ||||
| -rw-r--r-- | strings/ctype-ucs2.c | 19 | ||||
| -rw-r--r-- | strings/json_lib.c | 1553 |
3 files changed, 1569 insertions, 5 deletions
diff --git a/strings/CMakeLists.txt b/strings/CMakeLists.txt index 1e364bc951b..96de24b4770 100644 --- a/strings/CMakeLists.txt +++ b/strings/CMakeLists.txt @@ -23,7 +23,7 @@ SET(STRINGS_SOURCES bchange.c bmove_upp.c ctype-big5.c ctype-bin.c ctype-cp932.c str2int.c str_alloc.c strcend.c strend.c strfill.c strmake.c strmov.c strnmov.c strxmov.c strxnmov.c xml.c strmov_overlapp.c - my_strchr.c strcont.c strappend.c) + my_strchr.c strcont.c strappend.c json_lib.c) IF(NOT HAVE_STRNLEN) # OSX below 10.7 did not have strnlen diff --git a/strings/ctype-ucs2.c b/strings/ctype-ucs2.c index e154545e4f6..1c9dfe7324b 100644 --- a/strings/ctype-ucs2.c +++ b/strings/ctype-ucs2.c @@ -1190,10 +1190,13 @@ my_lengthsp_mb2(CHARSET_INFO *cs __attribute__((unused)), #endif /* HAVE_CHARSET_mb2*/ +/* + Next part is actually HAVE_CHARSET_utf16-specific, + but the JSON functions needed my_utf16_uni() + so the #ifdef was moved lower. +*/ -#ifdef HAVE_CHARSET_utf16 - /* D800..DB7F - Non-provate surrogate high (896 pages) DB80..DBFF - Private surrogate high (128 pages) @@ -1260,7 +1263,12 @@ static inline int my_weight_mb2_utf16mb2_general_ci(uchar b0, uchar b1) #undef IS_MB2_CHAR #undef IS_MB4_CHAR -static int +/* + These two functions are used in JSON library, so made exportable + and unconditionally compiled into the library. +*/ + +/*static*/ int my_utf16_uni(CHARSET_INFO *cs __attribute__((unused)), my_wc_t *pwc, const uchar *s, const uchar *e) { @@ -1293,7 +1301,7 @@ my_utf16_uni(CHARSET_INFO *cs __attribute__((unused)), } -static int +/*static*/ int my_uni_utf16(CHARSET_INFO *cs __attribute__((unused)), my_wc_t wc, uchar *s, uchar *e) { @@ -1323,6 +1331,9 @@ my_uni_utf16(CHARSET_INFO *cs __attribute__((unused)), } +#ifdef HAVE_CHARSET_utf16 + + static inline void my_tolower_utf16(MY_UNICASE_INFO *uni_plane, my_wc_t *wc) { diff --git a/strings/json_lib.c b/strings/json_lib.c new file mode 100644 index 00000000000..3f55280e3fa --- /dev/null +++ b/strings/json_lib.c @@ -0,0 +1,1553 @@ +#include <my_global.h> +#include <m_ctype.h> + + +#include "json_lib.h" + +/* + JSON escaping lets user specify UTF16 codes of characters. + So we're going to need the UTF16 charset capabilities. Let's import + them from the utf16 charset. +*/ +int my_utf16_uni(CHARSET_INFO *cs, + my_wc_t *pwc, const uchar *s, const uchar *e); +int my_uni_utf16(CHARSET_INFO *cs, my_wc_t wc, uchar *s, uchar *e); + + +void json_string_set_str(json_string_t *s, + const uchar *str, const uchar *end) +{ + s->c_str= str; + s->str_end= end; +} + + +void json_string_set_cs(json_string_t *s, CHARSET_INFO *i_cs) +{ + s->cs= i_cs; + s->error= 0; + s->wc= i_cs->cset->mb_wc; +} + + +static void json_string_setup(json_string_t *s, + CHARSET_INFO *i_cs, const uchar *str, + const uchar *end) +{ + json_string_set_cs(s, i_cs); + json_string_set_str(s, str, end); +} + + +enum json_char_classes { + C_EOS, /* end of string */ + C_LCURB, /* { */ + C_RCURB, /* } */ + C_LSQRB, /* [ */ + C_RSQRB, /* ] */ + C_COLON, /* : */ + C_COMMA, /* , */ + C_QUOTE, /* " */ + C_DIGIT, /* -0123456789 */ + C_LOW_F, /* 'f' (for "false") */ + C_LOW_N, /* 'n' (for "null") */ + C_LOW_T, /* 't' (for "true") */ + C_ETC, /* everything else */ + C_ERR, /* character disallowed in JSON */ + C_BAD, /* invalid character, charset handler cannot read it */ + NR_C_CLASSES, /* Counter for classes that handled with functions. */ + C_SPACE /* space. Doesn't need specific handlers, so after the counter.*/ +}; + + +/* + This array maps first 128 Unicode Code Points into classes. + The remaining Unicode characters should be mapped to C_ETC. +*/ + +static enum json_char_classes json_chr_map[128] = { + C_ERR, C_ERR, C_ERR, C_ERR, C_ERR, C_ERR, C_ERR, C_ERR, + C_ERR, C_SPACE, C_SPACE, C_ERR, C_ERR, C_SPACE, C_ERR, C_ERR, + C_ERR, C_ERR, C_ERR, C_ERR, C_ERR, C_ERR, C_ERR, C_ERR, + C_ERR, C_ERR, C_ERR, C_ERR, C_ERR, C_ERR, C_ERR, C_ERR, + + C_SPACE, C_ETC, C_QUOTE, C_ETC, C_ETC, C_ETC, C_ETC, C_ETC, + C_ETC, C_ETC, C_ETC, C_ETC, C_COMMA, C_DIGIT, C_ETC, C_ETC, + C_DIGIT, C_DIGIT, C_DIGIT, C_DIGIT, C_DIGIT, C_DIGIT, C_DIGIT, C_DIGIT, + C_DIGIT, C_DIGIT, C_COLON, C_ETC, C_ETC, C_ETC, C_ETC, C_ETC, + + C_ETC, C_ETC, C_ETC, C_ETC, C_ETC, C_ETC, C_ETC, C_ETC, + C_ETC, C_ETC, C_ETC, C_ETC, C_ETC, C_ETC, C_ETC, C_ETC, + C_ETC, C_ETC, C_ETC, C_ETC, C_ETC, C_ETC, C_ETC, C_ETC, + C_ETC, C_ETC, C_ETC, C_LSQRB, C_ETC, C_RSQRB, C_ETC, C_ETC, + + C_ETC, C_ETC, C_ETC, C_ETC, C_ETC, C_ETC, C_LOW_F, C_ETC, + C_ETC, C_ETC, C_ETC, C_ETC, C_ETC, C_ETC, C_LOW_N, C_ETC, + C_ETC, C_ETC, C_ETC, C_ETC, C_LOW_T, C_ETC, C_ETC, C_ETC, + C_ETC, C_ETC, C_ETC, C_LCURB, C_ETC, C_RCURB, C_ETC, C_ETC +}; + + +/* + JSON parser actually has more states than the 'enum json_states' + declares. But the rest of the states aren't seen to the user so let's + specify them here to avoid confusion. +*/ + +enum json_all_states { + JST_DONE= NR_JSON_USER_STATES, /* ok to finish */ + JST_OBJ_CONT= NR_JSON_USER_STATES+1, /* object continues */ + JST_ARRAY_CONT= NR_JSON_USER_STATES+2, /* array continues */ + JST_READ_VALUE= NR_JSON_USER_STATES+3, /* value is being read */ + NR_JSON_STATES= NR_JSON_USER_STATES+4 +}; + + +typedef int (*json_state_handler)(json_engine_t *); + + +/* The string is broken. */ +static int unexpected_eos(json_engine_t *j) +{ + j->s.error= JE_EOS; + return 1; +} + + +/* This symbol here breaks the JSON syntax. */ +static int syntax_error(json_engine_t *j) +{ + j->s.error= JE_SYN; + return 1; +} + + +/* Value of object. */ +static int mark_object(json_engine_t *j) +{ + j->state= JST_OBJ_START; + *(++j->stack_p)= JST_OBJ_CONT; + return 0; +} + + +/* Read value of object. */ +static int read_obj(json_engine_t *j) +{ + j->state= JST_OBJ_START; + j->value_type= JSON_VALUE_OBJECT; + j->value= j->value_begin; + *(++j->stack_p)= JST_OBJ_CONT; + return 0; +} + + +/* Value of array. */ +static int mark_array(json_engine_t *j) +{ + j->state= JST_ARRAY_START; + *(++j->stack_p)= JST_ARRAY_CONT; + j->value= j->value_begin; + return 0; +} + +/* Read value of object. */ +static int read_array(json_engine_t *j) +{ + j->state= JST_ARRAY_START; + j->value_type= JSON_VALUE_ARRAY; + j->value= j->value_begin; + *(++j->stack_p)= JST_ARRAY_CONT; + return 0; +} + + + +/* + Character classes inside the JSON string constant. + We mostly need this to parse escaping properly. + Escapings availabe in JSON are: + \" - quotation mark + \\ - backslash + \b - backspace UNICODE 8 + \f - formfeed UNICODE 12 + \n - newline UNICODE 10 + \r - carriage return UNICODE 13 + \t - horizontal tab UNICODE 9 + \u{four-hex-digits} - code in UCS16 character set +*/ +enum json_string_char_classes { + S_0= 0, + S_1= 1, + S_2= 2, + S_3= 3, + S_4= 4, + S_5= 5, + S_6= 6, + S_7= 7, + S_8= 8, + S_9= 9, + S_A= 10, + S_B= 11, + S_C= 12, + S_D= 13, + S_E= 14, + S_F= 15, + S_ETC= 36, /* rest of characters. */ + S_QUOTE= 37, + S_BKSL= 38, /* \ */ + S_ERR= 100, /* disallowed */ +}; + + +/* This maps characters to their types inside a string constant. */ +static enum json_string_char_classes json_instr_chr_map[128] = { + S_ERR, S_ERR, S_ERR, S_ERR, S_ERR, S_ERR, S_ERR, S_ERR, + S_ERR, S_ERR, S_ERR, S_ERR, S_ERR, S_ERR, S_ERR, S_ERR, + S_ERR, S_ERR, S_ERR, S_ERR, S_ERR, S_ERR, S_ERR, S_ERR, + S_ERR, S_ERR, S_ERR, S_ERR, S_ERR, S_ERR, S_ERR, S_ERR, + + S_ETC, S_ETC, S_QUOTE, S_ETC, S_ETC, S_ETC, S_ETC, S_ETC, + S_ETC, S_ETC, S_ETC, S_ETC, S_ETC, S_ETC, S_ETC, S_ETC, + S_0, S_1, S_2, S_3, S_4, S_5, S_6, S_7, + S_8, S_9, S_ETC, S_ETC, S_ETC, S_ETC, S_ETC, S_ETC, + + S_ETC, S_A, S_B, S_C, S_D, S_E, S_F, S_ETC, + S_ETC, S_ETC, S_ETC, S_ETC, S_ETC, S_ETC, S_ETC, S_ETC, + S_ETC, S_ETC, S_ETC, S_ETC, S_ETC, S_ETC, S_ETC, S_ETC, + S_ETC, S_ETC, S_ETC, S_ETC, S_BKSL, S_ETC, S_ETC, S_ETC, + + S_ETC, S_A, S_B, S_C, S_D, S_E, S_F, S_ETC, + S_ETC, S_ETC, S_ETC, S_ETC, S_ETC, S_ETC, S_ETC, S_ETC, + S_ETC, S_ETC, S_ETC, S_ETC, S_ETC, S_ETC, S_ETC, S_ETC, + S_ETC, S_ETC, S_ETC, S_ETC, S_ETC, S_ETC, S_ETC, S_ETC +}; + + +static int read_4_hexdigits(json_string_t *s, uchar *dest) +{ + int i, t, c_len; + for (i=0; i<4; i++) + { + if ((c_len= json_next_char(s)) <= 0) + return s->error= json_eos(s) ? JE_EOS : JE_BAD_CHR; + + if (s->c_next >= 128 || (t= json_instr_chr_map[s->c_next]) >= S_F) + return s->error= JE_SYN; + + s->c_str+= c_len; + dest[i/2]+= (i % 2) ? t : t*16; + } + return 0; +} + + +static int json_handle_esc(json_string_t *s) +{ + int t, c_len; + + if ((c_len= json_next_char(s)) <= 0) + return s->error= json_eos(s) ? JE_EOS : JE_BAD_CHR; + + s->c_str+= c_len; + switch (s->c_next) + { + case 'b': + s->c_next= 8; + return 0; + case 'f': + s->c_next= 12; + return 0; + case 'n': + s->c_next= 10; + return 0; + case 'r': + s->c_next= 13; + return 0; + case 't': + s->c_next= 9; + return 0; + } + + if (s->c_next < 128 && (t= json_instr_chr_map[s->c_next]) == S_ERR) + { + s->c_str-= c_len; + return s->error= JE_ESCAPING; + } + + + if (s->c_next != 'u') + return 0; + + { + /* + Read the four-hex-digits code. + If symbol is not in the Basic Multilingual Plane, we're reading + the string for the next four digits to compose the UTF-16 surrogate pair. + */ + uchar code[4]= {0,0,0,0}; + + if (read_4_hexdigits(s, code)) + return 1; + + if ((c_len= my_utf16_uni(0, &s->c_next, code, code+2)) == 2) + return 0; + + if (c_len != MY_CS_TOOSMALL4) + return s->error= JE_BAD_CHR; + + if ((c_len= json_next_char(s)) <= 0) + return s->error= json_eos(s) ? JE_EOS : JE_BAD_CHR; + if (s->c_next != '\\') + return s->error= JE_SYN; + + if ((c_len= json_next_char(s)) <= 0) + return s->error= json_eos(s) ? JE_EOS : JE_BAD_CHR; + if (s->c_next != 'u') + return s->error= JE_SYN; + + if (read_4_hexdigits(s, code+2)) + return 1; + + if ((c_len= my_utf16_uni(0, &s->c_next, code, code+4)) == 2) + return 0; + } + return s->error= JE_BAD_CHR; +} + + +int json_read_string_const_chr(json_string_t *js) +{ + int c_len; + + if ((c_len= json_next_char(js)) > 0) + { + js->c_str+= c_len; + return (js->c_next == '\\') ? json_handle_esc(js) : 0; + } + js->error= json_eos(js) ? JE_EOS : JE_BAD_CHR; + return 1; +} + + +static int skip_str_constant(json_engine_t *j) +{ + int t, c_len; + for (;;) + { + if ((c_len= json_next_char(&j->s)) > 0) + { + j->s.c_str+= c_len; + if (j->s.c_next >= 128 || ((t=json_instr_chr_map[j->s.c_next]) <= S_ETC)) + continue; + + if (j->s.c_next == '"') + break; + if (j->s.c_next == '\\') + { + if (json_handle_esc(&j->s)) + return 1; + continue; + } + /* Symbol not allowed in JSON. */ + return j->s.error= JE_NOT_JSON_CHR; + } + else + return j->s.error= json_eos(&j->s) ? JE_EOS : JE_BAD_CHR; + } + + j->state= *j->stack_p; + return 0; +} + + +/* Scalar string. */ +static int v_string(json_engine_t *j) +{ + return skip_str_constant(j) || json_scan_next(j); +} + + +/* Read scalar string. */ +static int read_strn(json_engine_t *j) +{ + j->value= j->s.c_str; + + if (skip_str_constant(j)) + return 1; + + j->state= *j->stack_p; + j->value_type= JSON_VALUE_STRING; + j->value_len= (j->s.c_str - j->value) - 1; + return 0; +} + + +/* + We have dedicated parser for numeric constants. It's similar + to the main JSON parser, we similarly define character classes, + map characters to classes and implement the state-per-class + table. Though we don't create functions that handle + particular classes, just specify what new state should parser + get in this case. +*/ +enum json_num_char_classes { + N_MINUS, + N_PLUS, + N_ZERO, + N_DIGIT, + N_POINT, + N_E, + N_END, + N_EEND, + N_ERR, + N_NUM_CLASSES +}; + + +static enum json_num_char_classes json_num_chr_map[128] = { + N_ERR, N_ERR, N_ERR, N_ERR, N_ERR, N_ERR, N_ERR, N_ERR, + N_ERR, N_END, N_END, N_ERR, N_ERR, N_END, N_ERR, N_ERR, + N_ERR, N_ERR, N_ERR, N_ERR, N_ERR, N_ERR, N_ERR, N_ERR, + N_ERR, N_ERR, N_ERR, N_ERR, N_ERR, N_ERR, N_ERR, N_ERR, + + N_END, N_EEND, N_EEND, N_EEND, N_EEND, N_EEND, N_EEND, N_EEND, + N_EEND, N_EEND, N_EEND, N_PLUS, N_END, N_MINUS, N_POINT, N_EEND, + N_ZERO, N_DIGIT, N_DIGIT, N_DIGIT, N_DIGIT, N_DIGIT, N_DIGIT, N_DIGIT, + N_DIGIT, N_DIGIT, N_EEND, N_EEND, N_EEND, N_EEND, N_EEND, N_EEND, + + N_EEND, N_EEND, N_EEND, N_EEND, N_EEND, N_E, N_EEND, N_EEND, + N_EEND, N_EEND, N_EEND, N_EEND, N_EEND, N_EEND, N_EEND, N_EEND, + N_EEND, N_EEND, N_EEND, N_EEND, N_EEND, N_EEND, N_EEND, N_EEND, + N_EEND, N_EEND, N_EEND, N_EEND, N_EEND, N_END, N_EEND, N_EEND, + + N_EEND, N_EEND, N_EEND, N_EEND, N_EEND, N_E, N_EEND, N_EEND, + N_EEND, N_EEND, N_EEND, N_EEND, N_EEND, N_EEND, N_EEND, N_EEND, + N_EEND, N_EEND, N_EEND, N_EEND, N_EEND, N_EEND, N_EEND, N_EEND, + N_EEND, N_EEND, N_EEND, N_EEND, N_EEND, N_END, N_EEND, N_EEND, +}; + + +enum json_num_states { + NS_OK, /* Number ended. */ + NS_GO, /* Initial state. */ + NS_GO1, /* If the number starts with '-'. */ + NS_Z, /* If the number starts with '0'. */ + NS_Z1, /* If the numbers starts with '-0'. */ + NS_INT, /* Integer part. */ + NS_FRAC,/* Fractional part. */ + NS_EX, /* Exponential part begins. */ + NS_EX1, /* Exponential part continues. */ + NS_NUM_STATES +}; + + +static int json_num_states[NS_NUM_STATES][N_NUM_CLASSES]= +{ +/* - + 0 1..9 POINT E END_OK ERROR */ +/*OK*/ { JE_SYN, JE_SYN, JE_SYN, JE_SYN, JE_SYN, JE_SYN, JE_SYN, JE_BAD_CHR }, +/*GO*/ { NS_GO1, JE_SYN, NS_Z, NS_INT, JE_SYN, JE_SYN, JE_SYN, JE_BAD_CHR }, +/*GO1*/ { JE_SYN, JE_SYN, NS_Z1, NS_INT, JE_SYN, JE_SYN, JE_SYN, JE_BAD_CHR }, +/*ZERO*/ { JE_SYN, JE_SYN, JE_SYN, JE_SYN, NS_FRAC, JE_SYN, NS_OK, JE_BAD_CHR }, +/*ZE1*/ { JE_SYN, JE_SYN, JE_SYN, JE_SYN, NS_FRAC, JE_SYN, JE_SYN, JE_BAD_CHR }, +/*INT*/ { JE_SYN, JE_SYN, NS_INT, NS_INT, NS_FRAC, NS_EX, NS_OK, JE_BAD_CHR }, +/*FRAC*/ { JE_SYN, JE_SYN, NS_FRAC, NS_FRAC,JE_SYN, NS_EX, NS_OK, JE_BAD_CHR }, +/*EX*/ { NS_EX1, NS_EX1, NS_EX1, NS_EX1, JE_SYN, JE_SYN, JE_SYN, JE_BAD_CHR }, +/*EX1*/ { JE_SYN, JE_SYN, NS_EX1, NS_EX1, JE_SYN, JE_SYN, JE_SYN, JE_BAD_CHR } +}; + + +static int skip_num_constant(json_engine_t *j) +{ + int state= json_num_states[NS_GO][json_num_chr_map[j->s.c_next]]; + int c_len; + + for (;;) + { + if ((c_len= json_next_char(&j->s)) > 0) + { + if ((state= json_num_states[state][json_num_chr_map[j->s.c_next]]) > 0) + { + j->s.c_str+= c_len; + continue; + } + break; + } + + if ((j->s.error= + json_eos(&j->s) ? json_num_states[state][N_END] : JE_BAD_CHR) < 0) + return 1; + else + break; + } + + j->state= *j->stack_p; + return 0; +} + + +/* Scalar numeric. */ +static int v_number(json_engine_t *j) +{ + return skip_num_constant(j) || json_scan_next(j); +} + + +/* Read numeric constant. */ +static int read_num(json_engine_t *j) +{ + j->value= j->value_begin; + if (skip_num_constant(j) == 0) + { + j->value_type= JSON_VALUE_NUMBER; + j->value_len= j->s.c_str - j->value_begin; + return 0; + } + return 1; +} + + +/* Check that the JSON string matches the argument and skip it. */ +static int skip_string_verbatim(json_string_t *s, const char *str) +{ + int c_len; + while (*str) + { + if ((c_len= json_next_char(s)) > 0) + { + if (s->c_next == (my_wc_t) *(str++)) + { + s->c_str+= c_len; + continue; + } + return JE_SYN; + } + return json_eos(s) ? JE_EOS : JE_BAD_CHR; + } + + return 0; +} + + +/* Scalar false. */ +static int v_false(json_engine_t *j) +{ + if (skip_string_verbatim(&j->s, "alse")) + return 1; + j->state= *j->stack_p; + return json_scan_next(j); +} + + +/* Scalar null. */ +static int v_null(json_engine_t *j) +{ + if (skip_string_verbatim(&j->s, "ull")) + return 1; + j->state= *j->stack_p; + return json_scan_next(j); +} + + +/* Scalar true. */ +static int v_true(json_engine_t *j) +{ + if (skip_string_verbatim(&j->s, "rue")) + return 1; + j->state= *j->stack_p; + return json_scan_next(j); +} + + +/* Read false. */ +static int read_false(json_engine_t *j) +{ + j->value_type= JSON_VALUE_FALSE; + j->value= j->value_begin; + j->state= *j->stack_p; + j->value_len= 5; + return skip_string_verbatim(&j->s, "alse"); +} + + +/* Read null. */ +static int read_null(json_engine_t *j) +{ + j->value_type= JSON_VALUE_NULL; + j->value= j->value_begin; + j->state= *j->stack_p; + j->value_len= 4; + return skip_string_verbatim(&j->s, "ull"); +} + + +/* Read true. */ +static int read_true(json_engine_t *j) +{ + j->value_type= JSON_VALUE_TRUE; + j->value= j->value_begin; + j->state= *j->stack_p; + j->value_len= 4; + return skip_string_verbatim(&j->s, "rue"); +} + + +/* Disallowed character. */ +static int not_json_chr(json_engine_t *j) +{ + j->s.error= JE_NOT_JSON_CHR; + return 1; +} + + +/* Bad character. */ +static int bad_chr(json_engine_t *j) +{ + j->s.error= JE_BAD_CHR; + return 1; +} + + +/* Correct finish. */ +static int done(json_engine_t *j __attribute__((unused))) +{ + return 1; +} + + +/* End of the object. */ +static int end_object(json_engine_t *j) +{ + j->stack_p--; + j->state= JST_OBJ_END; + return 0; +} + + +/* End of the array. */ +static int end_array(json_engine_t *j) +{ + j->stack_p--; + j->state= JST_ARRAY_END; + return 0; +} + + +/* Start reading key name. */ +static int read_keyname(json_engine_t *j) +{ + j->state= JST_KEY; + return 0; +} + + +static void get_first_nonspace(json_string_t *js, int *t_next, int *c_len) +{ + do + { + if ((*c_len= json_next_char(js)) <= 0) + *t_next= json_eos(js) ? C_EOS : C_BAD; + else + { + *t_next= (js->c_next < 128) ? json_chr_map[js->c_next] : C_ETC; + js->c_str+= *c_len; + } + } while (*t_next == C_SPACE); +} + + +/* Next key name. */ +static int next_key(json_engine_t *j) +{ + int t_next, c_len; + get_first_nonspace(&j->s, &t_next, &c_len); + + if (t_next == C_QUOTE) + { + j->state= JST_KEY; + return 0; + } + + j->s.error= (t_next == C_EOS) ? JE_EOS : + ((t_next == C_BAD) ? JE_BAD_CHR : + JE_SYN); + return 1; +} + + +/* Forward declarations. */ +static int skip_colon(json_engine_t *j); +static int skip_key(json_engine_t *j); +static int struct_end_cb(json_engine_t *j); +static int struct_end_qb(json_engine_t *j); +static int struct_end_cm(json_engine_t *j); +static int struct_end_eos(json_engine_t *j); + + +static int next_item(json_engine_t *j) +{ + j->state= JST_VALUE; + return 0; +} + + +static int array_item(json_engine_t *j) +{ + j->state= JST_VALUE; + j->s.c_str-= j->sav_c_len; + return 0; +} + + +static json_state_handler json_actions[NR_JSON_STATES][NR_C_CLASSES]= +/* + EOS { } [ ] + : , " -0..9 f + n t ETC ERR BAD +*/ +{ + {/*VALUE*/ + unexpected_eos, mark_object, syntax_error, mark_array, syntax_error, + syntax_error, syntax_error,v_string, v_number, v_false, + v_null, v_true, syntax_error, not_json_chr, bad_chr}, + {/*KEY*/ + unexpected_eos, skip_key, skip_key, skip_key, skip_key, + skip_key, skip_key, skip_colon, skip_key, skip_key, + skip_key, skip_key, skip_key, not_json_chr, bad_chr}, + {/*OBJ_START*/ + unexpected_eos, syntax_error, end_object, syntax_error, syntax_error, + syntax_error, syntax_error, read_keyname, syntax_error, syntax_error, + syntax_error, syntax_error, syntax_error, not_json_chr, bad_chr}, + {/*OBJ_END*/ + struct_end_eos, syntax_error, struct_end_cb, syntax_error, struct_end_qb, + syntax_error, struct_end_cm,syntax_error, syntax_error, syntax_error, + syntax_error, syntax_error, syntax_error, not_json_chr, bad_chr}, + {/*ARRAY_START*/ + unexpected_eos, array_item, syntax_error, array_item, end_array, + syntax_error, syntax_error, array_item, array_item, array_item, + array_item, array_item, syntax_error, not_json_chr, bad_chr}, + {/*ARRAY_END*/ + struct_end_eos, syntax_error, struct_end_cb, syntax_error, struct_end_qb, + syntax_error, struct_end_cm, syntax_error, syntax_error, syntax_error, + syntax_error, syntax_error, syntax_error, not_json_chr, bad_chr}, + {/*DONE*/ + done, syntax_error, syntax_error, syntax_error, syntax_error, + syntax_error, syntax_error, syntax_error, syntax_error, syntax_error, + syntax_error, syntax_error, syntax_error, not_json_chr, bad_chr}, + {/*OBJ_CONT*/ + unexpected_eos, syntax_error, end_object, syntax_error, end_array, + syntax_error, next_key, syntax_error, syntax_error, syntax_error, + syntax_error, syntax_error, syntax_error, not_json_chr, bad_chr}, + {/*ARRAY_CONT*/ + unexpected_eos, syntax_error, syntax_error, syntax_error, end_array, + syntax_error, next_item, syntax_error, syntax_error, syntax_error, + syntax_error, syntax_error, syntax_error, not_json_chr, bad_chr}, + {/*READ_VALUE*/ + unexpected_eos, read_obj, syntax_error, read_array, syntax_error, + syntax_error, syntax_error, read_strn, read_num, read_false, + read_null, read_true, syntax_error, not_json_chr, bad_chr}, +}; + + + +int json_scan_start(json_engine_t *je, + CHARSET_INFO *i_cs, const uchar *str, const uchar *end) +{ + json_string_setup(&je->s, i_cs, str, end); + je->stack[0]= JST_DONE; + je->stack_p= je->stack; + je->state= JST_VALUE; + return 0; +} + + +/* Skip colon and the value. */ +static int skip_colon(json_engine_t *j) +{ + int t_next, c_len; + + get_first_nonspace(&j->s, &t_next, &c_len); + + if (t_next == C_COLON) + { + get_first_nonspace(&j->s, &t_next, &c_len); + return json_actions[JST_VALUE][t_next](j); + } + + j->s.error= (t_next == C_EOS) ? JE_EOS : + ((t_next == C_BAD) ? JE_BAD_CHR: + JE_SYN); + + return 1; +} + + +/* Skip colon and the value. */ +static int skip_key(json_engine_t *j) +{ + int t_next, c_len; + while (json_read_keyname_chr(j) == 0) {} + + if (j->s.error) + return 1; + + get_first_nonspace(&j->s, &t_next, &c_len); + return json_actions[JST_VALUE][t_next](j); +} + + +/* + Handle EOS after the end of an object or array. + To do that we should pop the stack to see if + we are inside an object, or an array, and + run our 'state machine' accordingly. +*/ +static int struct_end_eos(json_engine_t *j) +{ return json_actions[*j->stack_p][C_EOS](j); } + + +/* + Handle '}' after the end of an object or array. + To do that we should pop the stack to see if + we are inside an object, or an array, and + run our 'state machine' accordingly. +*/ +static int struct_end_cb(json_engine_t *j) +{ return json_actions[*j->stack_p][C_RCURB](j); } + + +/* + Handle ']' after the end of an object or array. + To do that we should pop the stack to see if + we are inside an object, or an array, and + run our 'state machine' accordingly. +*/ +static int struct_end_qb(json_engine_t *j) +{ return json_actions[*j->stack_p][C_RSQRB](j); } + + +/* + Handle ',' after the end of an object or array. + To do that we should pop the stack to see if + we are inside an object, or an array, and + run our 'state machine' accordingly. +*/ +static int struct_end_cm(json_engine_t *j) +{ return json_actions[*j->stack_p][C_COMMA](j); } + + +int json_read_keyname_chr(json_engine_t *j) +{ + int c_len, t; + + if ((c_len= json_next_char(&j->s)) > 0) + { + j->s.c_str+= c_len; + if (j->s.c_next>= 128 || (t= json_instr_chr_map[j->s.c_next]) <= S_ETC) + return 0; + + switch (t) + { + case S_QUOTE: + for (;;) /* Skip spaces until ':'. */ + { + if ((c_len= json_next_char(&j->s) > 0)) + { + if (j->s.c_next == ':') + { + j->s.c_str+= c_len; + j->state= JST_VALUE; + return 1; + } + + if (j->s.c_next < 128 && json_chr_map[j->s.c_next] == C_SPACE) + { + j->s.c_str+= c_len; + continue; + } + j->s.error= JE_SYN; + break; + } + j->s.error= json_eos(&j->s) ? JE_EOS : JE_BAD_CHR; + break; + } + return 1; + case S_BKSL: + return json_handle_esc(&j->s); + case S_ERR: + j->s.c_str-= c_len; + j->s.error= JE_STRING_CONST; + return 1; + } + } + j->s.error= json_eos(&j->s) ? JE_EOS : JE_BAD_CHR; + return 1; +} + + +int json_read_value(json_engine_t *j) +{ + int t_next, c_len, res; + + if (j->state == JST_KEY) + { + while (json_read_keyname_chr(j) == 0) {} + + if (j->s.error) + return 1; + } + + get_first_nonspace(&j->s, &t_next, &c_len); + + j->value_begin= j->s.c_str-c_len; + res= json_actions[JST_READ_VALUE][t_next](j); + j->value_end= j->s.c_str; + return res; +} + + +int json_scan_next(json_engine_t *j) +{ + int t_next; + + get_first_nonspace(&j->s, &t_next, &j->sav_c_len); + return json_actions[j->state][t_next](j); +} + + +enum json_path_chr_classes { + P_EOS, /* end of string */ + P_USD, /* $ */ + P_ASTER, /* * */ + P_LSQRB, /* [ */ + P_RSQRB, /* ] */ + P_POINT, /* . */ + P_ZERO, /* 0 */ + P_DIGIT, /* 123456789 */ + P_L, /* l (for "lax") */ + P_S, /* s (for "strict") */ + P_SPACE, /* space */ + P_BKSL, /* \ */ + P_ETC, /* everything else */ + P_ERR, /* character disallowed in JSON*/ + P_BAD, /* invalid character */ + N_PATH_CLASSES, +}; + + +static enum json_path_chr_classes json_path_chr_map[128] = { + P_ERR, P_ERR, P_ERR, P_ERR, P_ERR, P_ERR, P_ERR, P_ERR, + P_ERR, P_SPACE, P_SPACE, P_ERR, P_ERR, P_SPACE, P_ERR, P_ERR, + P_ERR, P_ERR, P_ERR, P_ERR, P_ERR, P_ERR, P_ERR, P_ERR, + P_ERR, P_ERR, P_ERR, P_ERR, P_ERR, P_ERR, P_ERR, P_ERR, + + P_SPACE, P_ETC, P_ETC, P_ETC, P_USD, P_ETC, P_ETC, P_ETC, + P_ETC, P_ETC, P_ASTER, P_ETC, P_ETC, P_ETC, P_POINT, P_ETC, + P_ZERO, P_DIGIT, P_DIGIT, P_DIGIT, P_DIGIT, P_DIGIT, P_DIGIT, P_DIGIT, + P_DIGIT, P_DIGIT, P_ETC, P_ETC, P_ETC, P_ETC, P_ETC, P_ETC, + + P_ETC, P_ETC, P_ETC, P_ETC, P_ETC, P_ETC, P_ETC, P_ETC, + P_ETC, P_ETC, P_ETC, P_ETC, P_L, P_ETC, P_ETC, P_ETC, + P_ETC, P_ETC, P_S, P_ETC, P_ETC, P_ETC, P_ETC, P_ETC, + P_ETC, P_ETC, P_ETC, P_LSQRB, P_BKSL, P_RSQRB, P_ETC, P_ETC, + + P_ETC, P_ETC, P_ETC, P_ETC, P_ETC, P_ETC, P_ETC, P_ETC, + P_ETC, P_ETC, P_ETC, P_ETC, P_L, P_ETC, P_ETC, P_ETC, + P_ETC, P_ETC, P_S, P_ETC, P_ETC, P_ETC, P_ETC, P_ETC, + P_ETC, P_ETC, P_ETC, P_ETC, P_ETC, P_ETC, P_ETC, P_ETC +}; + + +enum json_path_states { + PS_GO, /* Initial state. */ + PS_LAX, /* Parse the 'lax' keyword. */ + PS_PT, /* New path's step begins. */ + PS_AR, /* Parse array step. */ + PS_AWD, /* Array wildcard. */ + PS_Z, /* '0' (as an array item number). */ + PS_INT, /* Parse integer (as an array item number). */ + PS_AS, /* Space. */ + PS_KEY, /* Key. */ + PS_KNM, /* Parse key name. */ + PS_KWD, /* Key wildcard. */ + N_PATH_STATES, /* Below are states that aren't in the transitions table. */ + PS_SCT, /* Parse the 'strict' keyword. */ + PS_EKY, /* '.' after the keyname so next step is the key. */ + PS_EAR, /* '[' after the keyname so next step is the array. */ + PS_ESC, /* Escaping in the keyname. */ + PS_OK, /* Path normally ended. */ + PS_KOK /* EOS after the keyname so end the path normally. */ +}; + + +static int json_path_transitions[N_PATH_STATES][N_PATH_CLASSES]= +{ +/* + EOS $, * [ ] . 0 + 1..9 L S SPACE \ ETC ERR + BAD +*/ +/* GO */ { JE_EOS, PS_PT, JE_SYN, JE_SYN, JE_SYN, JE_SYN, JE_SYN, + JE_SYN, PS_LAX, PS_SCT, PS_GO, JE_SYN, JE_SYN, JE_NOT_JSON_CHR, + JE_BAD_CHR}, +/* LAX */ { JE_EOS, JE_SYN, JE_SYN, JE_SYN, JE_SYN, JE_SYN, JE_SYN, + JE_SYN, PS_LAX, JE_SYN, PS_GO, JE_SYN, JE_SYN, JE_NOT_JSON_CHR, + JE_BAD_CHR}, +/* PT */ { PS_OK, JE_SYN, JE_SYN, PS_AR, JE_SYN, PS_KEY, JE_SYN, JE_SYN, + JE_SYN, JE_SYN, JE_SYN, JE_SYN, JE_SYN, JE_NOT_JSON_CHR, + JE_BAD_CHR}, +/* AR */ { JE_EOS, JE_SYN, PS_AWD, JE_SYN, PS_PT, JE_SYN, PS_Z, + PS_INT, JE_SYN, JE_SYN, PS_AR, JE_SYN, JE_SYN, JE_NOT_JSON_CHR, + JE_BAD_CHR}, +/* AWD */ { JE_EOS, JE_SYN, JE_SYN, JE_SYN, PS_PT, JE_SYN, JE_SYN, + JE_SYN, JE_SYN, JE_SYN, PS_AS, JE_SYN, JE_SYN, JE_NOT_JSON_CHR, + JE_BAD_CHR}, +/* Z */ { JE_EOS, JE_SYN, JE_SYN, JE_SYN, PS_PT, JE_SYN, JE_SYN, + JE_SYN, JE_SYN, JE_SYN, PS_AS, JE_SYN, JE_SYN, JE_NOT_JSON_CHR, + JE_BAD_CHR}, +/* INT */ { JE_EOS, JE_SYN, JE_SYN, JE_SYN, PS_PT, JE_SYN, PS_INT, + PS_INT, JE_SYN, JE_SYN, PS_AS, JE_SYN, JE_SYN, JE_NOT_JSON_CHR, + JE_BAD_CHR}, +/* AS */ { JE_EOS, JE_SYN, JE_SYN, JE_SYN, PS_PT, JE_SYN, JE_SYN, JE_SYN, + JE_SYN, JE_SYN, PS_AS, JE_SYN, JE_SYN, JE_NOT_JSON_CHR, + JE_BAD_CHR}, +/* KEY */ { JE_EOS, PS_KNM, PS_KWD, JE_SYN, PS_KNM, JE_SYN, PS_KNM, + PS_KNM, PS_KNM, PS_KNM, PS_KNM, JE_SYN, PS_KNM, JE_NOT_JSON_CHR, + JE_BAD_CHR}, +/* KNM */ { PS_KOK, PS_KNM, PS_KNM, PS_EAR, PS_KNM, PS_EKY, PS_KNM, + PS_KNM, PS_KNM, PS_KNM, PS_KNM, PS_ESC, PS_KNM, JE_NOT_JSON_CHR, + JE_BAD_CHR}, +/* KWD */ { PS_OK, JE_SYN, JE_SYN, PS_AR, JE_SYN, PS_EKY, JE_SYN, + JE_SYN, JE_SYN, JE_SYN, JE_SYN, JE_SYN, JE_SYN, JE_NOT_JSON_CHR, + JE_BAD_CHR} +}; + + +int json_path_setup(json_path_t *p, + CHARSET_INFO *i_cs, const uchar *str, const uchar *end) +{ + int c_len, t_next, state= PS_GO; + + json_string_setup(&p->s, i_cs, str, end); + + p->steps[0].type= JSON_PATH_ARRAY; + p->steps[0].wild= 1; + p->last_step= p->steps; + p->mode_strict= FALSE; + + do + { + if ((c_len= json_next_char(&p->s)) <= 0) + t_next= json_eos(&p->s) ? P_EOS : P_BAD; + else + t_next= (p->s.c_next >= 128) ? P_ETC : json_path_chr_map[p->s.c_next]; + + if ((state= json_path_transitions[state][t_next]) < 0) + return p->s.error= state; + + p->s.c_str+= c_len; + + switch (state) + { + case PS_LAX: + if ((p->s.error= skip_string_verbatim(&p->s, "ax"))) + return 1; + p->mode_strict= FALSE; + continue; + case PS_SCT: + if ((p->s.error= skip_string_verbatim(&p->s, "rict"))) + return 1; + p->mode_strict= TRUE; + state= PS_LAX; + continue; + case PS_AWD: + p->last_step->wild= 1; + continue; + case PS_INT: + p->last_step->n_item*= 10; + p->last_step->n_item+= p->s.c_next - '0'; + continue; + case PS_EKY: + p->last_step->key_end= p->s.c_str - c_len; + state= PS_KEY; + /* Note no 'continue' here. */ + case PS_KEY: + p->last_step++; + p->last_step->type= JSON_PATH_KEY; + p->last_step->wild= 0; + p->last_step->key= p->s.c_str; + continue; + case PS_EAR: + p->last_step->key_end= p->s.c_str - c_len; + state= PS_AR; + /* Note no 'continue' here. */ + case PS_AR: + p->last_step++; + p->last_step->type= JSON_PATH_ARRAY; + p->last_step->wild= 0; + p->last_step->n_item= 0; + continue; + case PS_KWD: + p->last_step->wild= 1; + continue; + case PS_ESC: + if (json_handle_esc(&p->s)) + return 1; + continue; + case PS_KOK: + p->last_step->key_end= p->s.c_str - c_len; + state= PS_OK; + break; + }; + } while (state != PS_OK); + + return 0; +} + + +int json_skip_level(json_engine_t *j) +{ + int ct= 0; + + while (json_scan_next(j) == 0) + { + switch (j->state) { + case JST_OBJ_START: + case JST_ARRAY_START: + ct++; + break; + case JST_OBJ_END: + case JST_ARRAY_END: + if (ct == 0) + return 0; + ct--; + break; + } + } + + return 1; +} + + +int json_skip_key(json_engine_t *j) +{ + if (json_read_value(j)) + return 1; + + if (json_value_scalar(j)) + return 0; + + return json_skip_level(j); +} + + +/* + Current step of the patch matches the JSON construction. + Now we should either stop the search or go to the next + step of the path. +*/ +static int handle_match(json_engine_t *je, json_path_t *p, + json_path_step_t **p_cur_step, uint *array_counters) +{ + DBUG_ASSERT(*p_cur_step < p->last_step); + + if (json_read_value(je)) + return 1; + + if (json_value_scalar(je)) + return 0; + + (*p_cur_step)++; + array_counters[*p_cur_step - p->steps]= 0; + + if ((int) je->value_type != (int) (*p_cur_step)->type) + { + (*p_cur_step)--; + return json_skip_level(je); + } + + return 0; +} + + +/* + Check if the name of the current JSON key matches + the step of the path. +*/ +static int json_key_matches(json_engine_t *je, json_string_t *k) +{ + while (json_read_keyname_chr(je) == 0) + { + if (json_read_string_const_chr(k) || + je->s.c_next != k->c_next) + return 0; + } + + if (json_read_string_const_chr(k)) + return 1; + + return 0; +} + + +int json_find_path(json_engine_t *je, + json_path_t *p, json_path_step_t **p_cur_step, + uint *array_counters) +{ + json_string_t key_name; + + json_string_set_cs(&key_name, p->s.cs); + + do + { + json_path_step_t *cur_step= *p_cur_step; + switch (je->state) + { + case JST_KEY: + DBUG_ASSERT(cur_step->type == JSON_PATH_KEY); + if (!cur_step->wild) + { + json_string_set_str(&key_name, cur_step->key, cur_step->key_end); + if (!json_key_matches(je, &key_name)) + { + if (json_skip_key(je)) + goto exit; + continue; + } + } + if (cur_step == p->last_step || + handle_match(je, p, p_cur_step, array_counters)) + goto exit; + break; + case JST_VALUE: + DBUG_ASSERT(cur_step->type == JSON_PATH_ARRAY); + if (cur_step->wild || + cur_step->n_item == array_counters[cur_step - p->steps]) + { + /* Array item matches. */ + if (cur_step == p->last_step || + handle_match(je, p, p_cur_step, array_counters)) + goto exit; + } + else + { + json_skip_array_item(je); + array_counters[cur_step - p->steps]++; + } + break; + case JST_OBJ_END: + case JST_ARRAY_END: + (*p_cur_step)--; + break; + default: + DBUG_ASSERT(0); + break; + }; + } while (json_scan_next(je) == 0); + + /* No luck. */ + return 1; + +exit: + return je->s.error; +} + + +int json_find_paths_first(json_engine_t *je, json_find_paths_t *state, + uint n_paths, json_path_t *paths, uint *path_depths) +{ + state->n_paths= n_paths; + state->paths= paths; + state->cur_depth= 0; + state->path_depths= path_depths; + return json_find_paths_next(je, state); +} + + +int json_find_paths_next(json_engine_t *je, json_find_paths_t *state) +{ + uint p_c; + int path_found, no_match_found; + do + { + switch (je->state) + { + case JST_KEY: + path_found= FALSE; + no_match_found= TRUE; + for (p_c=0; p_c < state->n_paths; p_c++) + { + json_path_step_t *cur_step; + if (state->path_depths[p_c] < + state->cur_depth /* Path already failed. */ || + (cur_step= state->paths[p_c].steps + state->cur_depth)->type != + JSON_PATH_KEY) + continue; + + if (!cur_step->wild) + { + json_string_t key_name; + json_string_setup(&key_name, state->paths[p_c].s.cs, + cur_step->key, cur_step->key_end); + if (!json_key_matches(je, &key_name)) + continue; + } + if (cur_step - state->paths[p_c].last_step == state->cur_depth) + path_found= TRUE; + else + { + no_match_found= FALSE; + state->path_depths[p_c]= state->cur_depth + 1; + } + } + if (path_found) + /* Return the result. */ + goto exit; + if (no_match_found) + { + /* No possible paths left to check. Just skip the level. */ + if (json_skip_level(je)) + goto exit; + } + + break; + case JST_VALUE: + path_found= FALSE; + no_match_found= TRUE; + for (p_c=0; p_c < state->n_paths; p_c++) + { + json_path_step_t *cur_step; + if (state->path_depths[p_c]< state->cur_depth /* Path already failed. */ || + (cur_step= state->paths[p_c].steps + state->cur_depth)->type != + JSON_PATH_ARRAY) + continue; + if (cur_step->wild || + cur_step->n_item == state->array_counters[state->cur_depth]) + { + /* Array item matches. */ + if (cur_step - state->paths[p_c].last_step == state->cur_depth) + path_found= TRUE; + else + { + no_match_found= FALSE; + state->path_depths[p_c]= state->cur_depth + 1; + } + } + } + + if (path_found) + goto exit; + + if (no_match_found) + json_skip_array_item(je); + + state->array_counters[state->cur_depth]++; + break; + case JST_OBJ_START: + case JST_ARRAY_START: + for (p_c=0; p_c < state->n_paths; p_c++) + { + if (state->path_depths[p_c] < state->cur_depth) + /* Path already failed. */ + continue; + if (state->paths[p_c].steps[state->cur_depth].type == + (je->state == JST_OBJ_START) ? JSON_PATH_KEY : JSON_PATH_ARRAY) + state->path_depths[p_c]++; + } + state->cur_depth++; + break; + case JST_OBJ_END: + case JST_ARRAY_END: + for (p_c=0; p_c < state->n_paths; p_c++) + { + if (state->path_depths[p_c] < state->cur_depth) + continue; + state->path_depths[p_c]--; + } + state->cur_depth--; + break; + default: + DBUG_ASSERT(0); + break; + }; + } while (json_scan_next(je) == 0); + + /* No luck. */ + return 1; + +exit: + return je->s.error; +} + + +int json_append_ascii(CHARSET_INFO *json_cs, + uchar *json, uchar *json_end, + const uchar *ascii, const uchar *ascii_end) +{ + const uchar *json_start= json; + while (ascii < ascii_end) + { + int c_len; + if ((c_len= json_cs->cset->wc_mb(json_cs, (my_wc_t) *ascii, + json, json_end)) > 0) + { + json+= c_len; + ascii++; + continue; + } + + /* Error return. */ + return c_len; + } + + return json - json_start; +} + + +int json_unescape(CHARSET_INFO *json_cs, + const uchar *json_str, const uchar *json_end, + CHARSET_INFO *res_cs, uchar *res, uchar *res_end) +{ + json_string_t s; + json_string_setup(&s, json_cs, json_str, json_end); + while (json_read_string_const_chr(&s) == 0) + { + int c_len; + if ((c_len= res_cs->cset->wc_mb(res_cs, s.c_next, res, res_end)) > 0) + { + res+= c_len; + continue; + } + if (c_len == MY_CS_ILUNI) + { + /* + Result charset doesn't support the json's character. + Let's replace it with the '?' symbol. + */ + if ((c_len= res_cs->cset->wc_mb(res_cs, '?', res, res_end)) > 0) + { + res+= c_len; + continue; + } + } + /* Result buffer is too small. */ + return -1; + } + + return s.error ? 1 : 0; +} + + +/* When we need to replace a character with the escaping. */ +enum json_esc_char_classes { + ESC_= 0, /* No need to escape. */ + ESC_U= 'u', /* Character not allowed in JSON. Always escape as \uXXXX. */ + ESC_B= 'b', /* Backspace. Escape as \b */ + ESC_F= 'f', /* Formfeed. Escape as \f */ + ESC_N= 'n', /* Newline. Escape as \n */ + ESC_R= 'r', /* Return. Escape as \r */ + ESC_T= 't', /* Tab. Escape as \s */ + ESC_BS= '\\' /* Backslash or '"'. Escape by the \\ prefix. */ +}; + + +/* This specifies how we should escape the character. */ +static enum json_esc_char_classes json_escape_chr_map[0x60] = { + ESC_U, ESC_U, ESC_U, ESC_U, ESC_U, ESC_U, ESC_U, ESC_U, + ESC_B, ESC_T, ESC_N, ESC_U, ESC_F, ESC_R, ESC_U, ESC_U, + ESC_U, ESC_U, ESC_U, ESC_U, ESC_U, ESC_U, ESC_U, ESC_U, + ESC_U, ESC_U, ESC_U, ESC_U, ESC_U, ESC_U, ESC_U, ESC_U, + + ESC_, ESC_, ESC_BS, ESC_, ESC_, ESC_, ESC_, ESC_, + ESC_, ESC_, ESC_, ESC_, ESC_, ESC_, ESC_, ESC_, + ESC_, ESC_, ESC_, ESC_, ESC_, ESC_, ESC_, ESC_, + ESC_, ESC_, ESC_, ESC_, ESC_, ESC_, ESC_, ESC_, + + ESC_, ESC_, ESC_, ESC_, ESC_, ESC_, ESC_, ESC_, + ESC_, ESC_, ESC_, ESC_, ESC_, ESC_, ESC_, ESC_, + ESC_, ESC_, ESC_, ESC_, ESC_, ESC_, ESC_, ESC_, + ESC_, ESC_, ESC_, ESC_, ESC_BS, ESC_, ESC_, ESC_, +}; + + +static const char hexconv[16] = "0123456789ABCDEF"; + + +int json_escape(CHARSET_INFO *str_cs, + const uchar *str, const uchar *str_end, + CHARSET_INFO *json_cs, uchar *json, uchar *json_end) +{ + const uchar *json_start= json; + + while (str < str_end) + { + my_wc_t c_chr; + int c_len; + if ((c_len= str_cs->cset->mb_wc(str_cs, &c_chr, str, str_end)) > 0) + { + enum json_esc_char_classes c_class; + + str+= c_len; + if (c_chr > 0x60 || (c_class= json_escape_chr_map[c_chr]) == ESC_) + { + if ((c_len= json_cs->cset->wc_mb(json_cs, c_chr, json, json_end)) > 0) + { + json+= c_len; + continue; + } + if (c_len < 0) + { + /* JSON buffer is depleted. */ + return -1; + } + + /* JSON charset cannot convert this character. */ + c_class= ESC_U; + } + + if ((c_len= json_cs->cset->wc_mb(json_cs, '\\', json, json_end)) <= 0 || + (c_len= json_cs->cset->wc_mb(json_cs, + (c_class == ESC_BS) ? c_chr : c_class, + json+= c_len, json_end)) <= 0) + { + /* JSON buffer is depleted. */ + return -1; + } + json+= c_len; + + if (c_class != ESC_U) + continue; + + { + /* We have to use /uXXXX escaping. */ + uchar utf16buf[4]; + uchar code_str[8]; + int u_len= my_uni_utf16(0, c_chr, utf16buf, utf16buf + 4); + + code_str[0]= hexconv[utf16buf[0] >> 4]; + code_str[1]= hexconv[utf16buf[0] & 15]; + code_str[2]= hexconv[utf16buf[1] >> 4]; + code_str[3]= hexconv[utf16buf[1] & 15]; + + if (u_len > 2) + { + code_str[4]= hexconv[utf16buf[2] >> 4]; + code_str[5]= hexconv[utf16buf[2] & 15]; + code_str[6]= hexconv[utf16buf[3] >> 4]; + code_str[7]= hexconv[utf16buf[3] & 15]; + } + + if ((c_len= json_append_ascii(json_cs, json, json_end, + code_str, code_str+u_len*2)) > 0) + { + json+= c_len; + continue; + } + /* JSON buffer is depleted. */ + return -1; + } + } + } + + return json - json_start; +} |