File size: 14,054 Bytes
2b6ccf8 | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 | //
// jWrite.c version 1v2
//
// A *really* simple JSON writer in C
//
// see: jWrite.h for info
//
// TonyWilk, Mar 2015
//
#include <stddef.h>
#include <stdio.h>
#include <string.h> // memset()
#include <stdint.h>
#define JW_GLOBAL_CONTROL_STRUCT
#include "jWrite.h"
// the jWrite functions take the above jWriteControl structure pointer
// to maintain state while writing a JSON string.
//
// You can opt to use a single global instance of a jWriteControl structure
// which simplifies the function parameters or to supply your own structure
//
#ifdef JW_GLOBAL_CONTROL_STRUCT
struct jWriteControl g_jWriteControl; // global control struct
#define JWC_DECL // function parameter decl is empty
#define JWC_DECL0
#define JWC(x) g_jWriteControl.x // functions access global
#define JWC_PARAM // pointer to struct is empty
#define JWC_PARAM0
#else
#define JWC_DECL struct jWriteControl *jwc, // function parameter is ptr to control struct
#define JWC_DECL0 struct jWriteControl *jwc // function parameter, no params
#define JWC(x) jwc->x // functions use pointer
#define JWC_PARAM jwc, // pointer to stuct
#define JWC_PARAM0 jwc // pointer to stuct, no params
#endif
//------------------------------------------
// Internal functions
//
void jwPutch( JWC_DECL char c );
void jwPutstr( JWC_DECL const char *str );
void jwPutraw( JWC_DECL const char *str );
void modp_itoa10(int32_t value, char* str);
void modp_dtoa2(double value, char* str, int prec);
void jwPretty( JWC_DECL0 );
enum jwNodeType jwPop( JWC_DECL0 );
void jwPush( JWC_DECL enum jwNodeType nodeType );
//------------------------------------------
// jwOpen
// - open writing of JSON starting with rootType = JW_OBJECT or JW_ARRAY
// - initialise with user string buffer of length buflen
// - isPretty=JW_PRETTY adds \n and spaces to prettify output (else JW_COMPACT)
//
void jwOpen( JWC_DECL char *buffer, unsigned int buflen,
enum jwNodeType rootType, int isPretty )
{
memset( buffer, 0, buflen ); // zap the whole destination buffer
JWC(buffer)= buffer;
JWC(buflen)= buflen;
JWC(bufp)= buffer;
JWC(nodeStack)[0].nodeType= rootType;
JWC(nodeStack)[0].elementNo= 0;
JWC(stackpos)=0;
JWC(error)= JWRITE_OK;
JWC(callNo)= 1;
JWC(isPretty)= isPretty;
jwPutch( JWC_PARAM (rootType==JW_OBJECT) ? '{' : '[' );
}
//------------------------------------------
// jwClose
// - closes the root JSON object started by jwOpen()
// - returns error code
//
int jwClose( JWC_DECL0 )
{
if( JWC(error) == JWRITE_OK )
{
if( JWC(stackpos) == 0 )
{
enum jwNodeType node= JWC(nodeStack)[0].nodeType;
if( JWC(isPretty) )
jwPutch( JWC_PARAM '\n' );
jwPutch( JWC_PARAM (node == JW_OBJECT) ? '}' : ']');
}else{
JWC(error)= JWRITE_NEST_ERROR; // nesting error, not all objects closed when jwClose() called
}
}
return JWC(error);
}
//------------------------------------------
// End the current array/object
//
int jwEnd( JWC_DECL0 )
{
if( JWC(error) == JWRITE_OK )
{
enum jwNodeType node;
int lastElemNo= JWC(nodeStack)[JWC(stackpos)].elementNo;
node= jwPop( JWC_PARAM0 );
if( lastElemNo > 0 )
jwPretty( JWC_PARAM0 );
jwPutch( JWC_PARAM (node == JW_OBJECT) ? '}' : ']');
}
return JWC(error);
}
//------------------------------------------
// jwErrorPos
// - Returns position of error: the nth call to a jWrite function
//
int jwErrorPos( JWC_DECL0 )
{
return JWC(callNo);
}
//------------------------------------------
// Object insert functions
//
int _jwObj( JWC_DECL const char *key );
// put raw string to object (i.e. contents of rawtext without quotes)
//
void jwObj_raw( JWC_DECL const char *key, const char *rawtext )
{
if(_jwObj( JWC_PARAM key ) == JWRITE_OK)
jwPutraw( JWC_PARAM rawtext);
}
// put "quoted" string to object
//
void jwObj_string( JWC_DECL const char *key, const char *value )
{
if(_jwObj( JWC_PARAM key ) == JWRITE_OK)
jwPutstr( JWC_PARAM value );
}
void jwObj_int( JWC_DECL const char *key, int value )
{
modp_itoa10( value, JWC(tmpbuf) );
jwObj_raw( JWC_PARAM key, JWC(tmpbuf) );
}
void jwObj_double( JWC_DECL const char *key, double value )
{
modp_dtoa2( value, JWC(tmpbuf), 6 );
jwObj_raw( JWC_PARAM key, JWC(tmpbuf) );
}
void jwObj_bool( JWC_DECL const char *key, int oneOrZero )
{
jwObj_raw( JWC_PARAM key, (oneOrZero) ? "true" : "false" );
}
void jwObj_null( JWC_DECL const char *key )
{
jwObj_raw( JWC_PARAM key, "null" );
}
// put Object in Object
//
void jwObj_object( JWC_DECL const char *key )
{
if(_jwObj( JWC_PARAM key ) == JWRITE_OK)
{
jwPutch( JWC_PARAM '{' );
jwPush( JWC_PARAM JW_OBJECT );
}
}
// put Array in Object
//
void jwObj_array( JWC_DECL const char *key )
{
if(_jwObj( JWC_PARAM key ) == JWRITE_OK)
{
jwPutch( JWC_PARAM '[' );
jwPush( JWC_PARAM JW_ARRAY );
}
}
//------------------------------------------
// Array insert functions
//
int _jwArr( JWC_DECL0 );
// put raw string to array (i.e. contents of rawtext without quotes)
//
void jwArr_raw( JWC_DECL const char *rawtext )
{
if(_jwArr( JWC_PARAM0 ) == JWRITE_OK)
jwPutraw( JWC_PARAM rawtext);
}
// put "quoted" string to array
//
void jwArr_string( JWC_DECL const char *value )
{
if(_jwArr( JWC_PARAM0 ) == JWRITE_OK)
jwPutstr( JWC_PARAM value );
}
void jwArr_int( JWC_DECL int value )
{
modp_itoa10( value, JWC(tmpbuf) );
jwArr_raw( JWC_PARAM JWC(tmpbuf) );
}
void jwArr_double( JWC_DECL double value )
{
modp_dtoa2( value, JWC(tmpbuf), 6 );
jwArr_raw( JWC_PARAM JWC(tmpbuf) );
}
void jwArr_bool( JWC_DECL int oneOrZero )
{
jwArr_raw( JWC_PARAM (oneOrZero) ? "true" : "false" );
}
void jwArr_null( JWC_DECL0 )
{
jwArr_raw( JWC_PARAM "null" );
}
void jwArr_object( JWC_DECL0 )
{
if(_jwArr( JWC_PARAM0 ) == JWRITE_OK)
{
jwPutch( JWC_PARAM '{' );
jwPush( JWC_PARAM JW_OBJECT );
}
}
void jwArr_array( JWC_DECL0 )
{
if(_jwArr( JWC_PARAM0 ) == JWRITE_OK)
{
jwPutch( JWC_PARAM '[' );
jwPush( JWC_PARAM JW_ARRAY );
}
}
//------------------------------------------
// jwErrorToString
// - returns string describing error code
//
char *jwErrorToString( int err )
{
switch( err )
{
case JWRITE_OK: return "OK";
case JWRITE_BUF_FULL: return "output buffer full";
case JWRITE_NOT_ARRAY: return "tried to write Array value into Object";
case JWRITE_NOT_OBJECT: return "tried to write Object key/value into Array";
case JWRITE_STACK_FULL: return "array/object nesting > JWRITE_STACK_DEPTH";
case JWRITE_STACK_EMPTY:return "stack underflow error (too many 'end's)";
case JWRITE_NEST_ERROR: return "nesting error, not all objects closed when jwClose() called";
}
return "Unknown error";
}
//============================================================================
// Internal functions
//
void jwPretty( JWC_DECL0 )
{
int i;
if( JWC(isPretty) )
{
jwPutch( JWC_PARAM '\n' );
for( i=0; i<JWC(stackpos)+1; i++ )
jwPutraw( JWC_PARAM " " );
}
}
// Push / Pop node stack
//
void jwPush( JWC_DECL enum jwNodeType nodeType )
{
if( (JWC(stackpos)+1) >= JWRITE_STACK_DEPTH )
JWC(error)= JWRITE_STACK_FULL; // array/object nesting > JWRITE_STACK_DEPTH
else
{
JWC(nodeStack[++JWC(stackpos)]).nodeType= nodeType;
JWC(nodeStack[JWC(stackpos)]).elementNo= 0;
}
}
enum jwNodeType jwPop( JWC_DECL0 )
{
enum jwNodeType retval= JWC(nodeStack[JWC(stackpos)]).nodeType;
if( JWC(stackpos) == 0 )
JWC(error)= JWRITE_STACK_EMPTY; // stack underflow error (too many 'end's)
else
JWC(stackpos)--;
return retval;
}
void jwPutch( JWC_DECL char c )
{
if( (unsigned int)(JWC(bufp) - JWC(buffer)) >= JWC(buflen) )
{
JWC(error)= JWRITE_BUF_FULL;
}else{
*JWC(bufp)++ = c;
}
}
// put string enclosed in quotes
//
void jwPutstr( JWC_DECL const char *str )
{
jwPutch( JWC_PARAM '\"' );
while( *str != '\0' )
jwPutch( JWC_PARAM *str++ );
jwPutch( JWC_PARAM '\"' );
}
// put raw string
//
void jwPutraw( JWC_DECL const char *str )
{
while( *str != '\0' )
jwPutch( JWC_PARAM *str++ );
}
// *common Object function*
// - checks error
// - checks current node is OBJECT
// - adds comma if reqd
// - adds "key" :
//
int _jwObj( JWC_DECL const char *key )
{
if(JWC(error) == JWRITE_OK)
{
JWC(callNo)++;
if( JWC(nodeStack)[JWC(stackpos)].nodeType != JW_OBJECT )
JWC(error)= JWRITE_NOT_OBJECT; // tried to write Object key/value into Array
else if( JWC(nodeStack)[JWC(stackpos)].elementNo++ > 0 )
jwPutch( JWC_PARAM ',' );
jwPretty( JWC_PARAM0 );
jwPutstr( JWC_PARAM key );
jwPutch( JWC_PARAM ':' );
if( JWC(isPretty) )
jwPutch( JWC_PARAM ' ' );
}
return JWC(error);
}
// *common Array function*
// - checks error
// - checks current node is ARRAY
// - adds comma if reqd
//
int _jwArr( JWC_DECL0 )
{
if(JWC(error) == JWRITE_OK)
{
JWC(callNo)++;
if( JWC(nodeStack)[JWC(stackpos)].nodeType != JW_ARRAY )
JWC(error)= JWRITE_NOT_ARRAY; // tried to write array value into Object
else if( JWC(nodeStack)[JWC(stackpos)].elementNo++ > 0 )
jwPutch( JWC_PARAM ',' );
jwPretty( JWC_PARAM0 );
}
return JWC(error);
}
//=================================================================
//
// modp value-to-string functions
// - modified for C89
//
// We use these functions as they are a lot faster than sprintf()
//
// Origin of these routines:
/*
* <pre>
* Copyright © 2007, Nick Galbreath -- nickg [at] modp [dot] com
* All rights reserved.
* http://code.google.com/p/stringencoders/
* Released under the bsd license.
* </pre>
*/
static void strreverse(char* begin, char* end)
{
char aux;
while (end > begin)
aux = *end, *end-- = *begin, *begin++ = aux;
}
/** \brief convert an signed integer to char buffer
*
* \param[in] value
* \param[out] buf the output buffer. Should be 16 chars or more.
*/
void modp_itoa10(int32_t value, char* str)
{
char* wstr=str;
// Take care of sign
unsigned int uvalue = (value < 0) ? -value : value;
// Conversion. Number is reversed.
do *wstr++ = (char)(48 + (uvalue % 10)); while(uvalue /= 10);
if (value < 0) *wstr++ = '-';
*wstr='\0';
// Reverse string
strreverse(str,wstr-1);
}
/**
* Powers of 10
* 10^0 to 10^9
*/
static const double pow10[] = {1, 10, 100, 1000, 10000, 100000, 1000000,
10000000, 100000000, 1000000000};
/** \brief convert a floating point number to char buffer with a
* variable-precision format, and no trailing zeros
*
* This is similar to "%.[0-9]f" in the printf style, except it will
* NOT include trailing zeros after the decimal point. This type
* of format oddly does not exists with printf.
*
* If the input value is greater than 1<<31, then the output format
* will be switched exponential format.
*
* \param[in] value
* \param[out] buf The allocated output buffer. Should be 32 chars or more.
* \param[in] precision Number of digits to the right of the decimal point.
* Can only be 0-9.
*/
void modp_dtoa2(double value, char* str, int prec)
{
/* if input is larger than thres_max, revert to exponential */
const double thres_max = (double)(0x7FFFFFFF);
int count;
double diff = 0.0;
char* wstr = str;
int neg= 0;
int whole;
double tmp;
uint32_t frac;
/* Hacky test for NaN
* under -fast-math this won't work, but then you also won't
* have correct nan values anyways. The alternative is
* to link with libmath (bad) or hack IEEE double bits (bad)
*/
if (! (value == value)) {
str[0] = 'n'; str[1] = 'a'; str[2] = 'n'; str[3] = '\0';
return;
}
if (prec < 0) {
prec = 0;
} else if (prec > 9) {
/* precision of >= 10 can lead to overflow errors */
prec = 9;
}
/* we'll work in positive values and deal with the
negative sign issue later */
if (value < 0) {
neg = 1;
value = -value;
}
whole = (int) value;
tmp = (value - whole) * pow10[prec];
frac = (uint32_t)(tmp);
diff = tmp - frac;
if (diff > 0.5) {
++frac;
/* handle rollover, e.g. case 0.99 with prec 1 is 1.0 */
if (frac >= pow10[prec]) {
frac = 0;
++whole;
}
} else if (diff == 0.5 && ((frac == 0) || (frac & 1))) {
/* if halfway, round up if odd, OR
if last digit is 0. That last part is strange */
++frac;
}
/* for very large numbers switch back to native sprintf for exponentials.
anyone want to write code to replace this? */
/*
normal printf behavior is to print EVERY whole number digit
which can be 100s of characters overflowing your buffers == bad
*/
if (value > thres_max) {
sprintf(str, "%e", neg ? -value : value);
return;
}
if (prec == 0) {
diff = value - whole;
if (diff > 0.5) {
/* greater than 0.5, round up, e.g. 1.6 -> 2 */
++whole;
} else if (diff == 0.5 && (whole & 1)) {
/* exactly 0.5 and ODD, then round up */
/* 1.5 -> 2, but 2.5 -> 2 */
++whole;
}
//vvvvvvvvvvvvvvvvvvv Diff from modp_dto2
} else if (frac) {
count = prec;
// now do fractional part, as an unsigned number
// we know it is not 0 but we can have leading zeros, these
// should be removed
while (!(frac % 10)) {
--count;
frac /= 10;
}
//^^^^^^^^^^^^^^^^^^^ Diff from modp_dto2
// now do fractional part, as an unsigned number
do {
--count;
*wstr++ = (char)(48 + (frac % 10));
} while (frac /= 10);
// add extra 0s
while (count-- > 0) *wstr++ = '0';
// add decimal
*wstr++ = '.';
}
// do whole part
// Take care of sign
// Conversion. Number is reversed.
do *wstr++ = (char)(48 + (whole % 10)); while (whole /= 10);
if (neg) {
*wstr++ = '-';
}
*wstr='\0';
strreverse(str, wstr-1);
}
//=================================================================
/* end of jWrite.c */
|