Jeff Hostetler | 7545941 | 2018-07-13 16:54:08 +0000 | [diff] [blame] | 1 | #include "cache.h" |
| 2 | #include "json-writer.h" |
| 3 | |
| 4 | void jw_init(struct json_writer *jw) |
| 5 | { |
| 6 | strbuf_init(&jw->json, 0); |
| 7 | strbuf_init(&jw->open_stack, 0); |
| 8 | jw->need_comma = 0; |
| 9 | jw->pretty = 0; |
| 10 | } |
| 11 | |
| 12 | void jw_release(struct json_writer *jw) |
| 13 | { |
| 14 | strbuf_release(&jw->json); |
| 15 | strbuf_release(&jw->open_stack); |
| 16 | } |
| 17 | |
| 18 | /* |
| 19 | * Append JSON-quoted version of the given string to 'out'. |
| 20 | */ |
| 21 | static void append_quoted_string(struct strbuf *out, const char *in) |
| 22 | { |
| 23 | unsigned char c; |
| 24 | |
| 25 | strbuf_addch(out, '"'); |
| 26 | while ((c = *in++) != '\0') { |
| 27 | if (c == '"') |
| 28 | strbuf_addstr(out, "\\\""); |
| 29 | else if (c == '\\') |
| 30 | strbuf_addstr(out, "\\\\"); |
| 31 | else if (c == '\n') |
| 32 | strbuf_addstr(out, "\\n"); |
| 33 | else if (c == '\r') |
| 34 | strbuf_addstr(out, "\\r"); |
| 35 | else if (c == '\t') |
| 36 | strbuf_addstr(out, "\\t"); |
| 37 | else if (c == '\f') |
| 38 | strbuf_addstr(out, "\\f"); |
| 39 | else if (c == '\b') |
| 40 | strbuf_addstr(out, "\\b"); |
| 41 | else if (c < 0x20) |
| 42 | strbuf_addf(out, "\\u%04x", c); |
| 43 | else |
| 44 | strbuf_addch(out, c); |
| 45 | } |
| 46 | strbuf_addch(out, '"'); |
| 47 | } |
| 48 | |
| 49 | static void indent_pretty(struct json_writer *jw) |
| 50 | { |
| 51 | int k; |
| 52 | |
| 53 | for (k = 0; k < jw->open_stack.len; k++) |
| 54 | strbuf_addstr(&jw->json, " "); |
| 55 | } |
| 56 | |
| 57 | /* |
| 58 | * Begin an object or array (either top-level or nested within the currently |
| 59 | * open object or array). |
| 60 | */ |
| 61 | static void begin(struct json_writer *jw, char ch_open, int pretty) |
| 62 | { |
| 63 | jw->pretty = pretty; |
| 64 | |
| 65 | strbuf_addch(&jw->json, ch_open); |
| 66 | |
| 67 | strbuf_addch(&jw->open_stack, ch_open); |
| 68 | jw->need_comma = 0; |
| 69 | } |
| 70 | |
| 71 | /* |
| 72 | * Assert that the top of the open-stack is an object. |
| 73 | */ |
| 74 | static void assert_in_object(const struct json_writer *jw, const char *key) |
| 75 | { |
| 76 | if (!jw->open_stack.len) |
| 77 | BUG("json-writer: object: missing jw_object_begin(): '%s'", key); |
| 78 | if (jw->open_stack.buf[jw->open_stack.len - 1] != '{') |
| 79 | BUG("json-writer: object: not in object: '%s'", key); |
| 80 | } |
| 81 | |
| 82 | /* |
| 83 | * Assert that the top of the open-stack is an array. |
| 84 | */ |
| 85 | static void assert_in_array(const struct json_writer *jw) |
| 86 | { |
| 87 | if (!jw->open_stack.len) |
| 88 | BUG("json-writer: array: missing jw_array_begin()"); |
| 89 | if (jw->open_stack.buf[jw->open_stack.len - 1] != '[') |
| 90 | BUG("json-writer: array: not in array"); |
| 91 | } |
| 92 | |
| 93 | /* |
| 94 | * Add comma if we have already seen a member at this level. |
| 95 | */ |
| 96 | static void maybe_add_comma(struct json_writer *jw) |
| 97 | { |
| 98 | if (jw->need_comma) |
| 99 | strbuf_addch(&jw->json, ','); |
| 100 | else |
| 101 | jw->need_comma = 1; |
| 102 | } |
| 103 | |
| 104 | static void fmt_double(struct json_writer *jw, int precision, |
| 105 | double value) |
| 106 | { |
| 107 | if (precision < 0) { |
| 108 | strbuf_addf(&jw->json, "%f", value); |
| 109 | } else { |
| 110 | struct strbuf fmt = STRBUF_INIT; |
| 111 | strbuf_addf(&fmt, "%%.%df", precision); |
| 112 | strbuf_addf(&jw->json, fmt.buf, value); |
| 113 | strbuf_release(&fmt); |
| 114 | } |
| 115 | } |
| 116 | |
| 117 | static void object_common(struct json_writer *jw, const char *key) |
| 118 | { |
| 119 | assert_in_object(jw, key); |
| 120 | maybe_add_comma(jw); |
| 121 | |
| 122 | if (jw->pretty) { |
| 123 | strbuf_addch(&jw->json, '\n'); |
| 124 | indent_pretty(jw); |
| 125 | } |
| 126 | |
| 127 | append_quoted_string(&jw->json, key); |
| 128 | strbuf_addch(&jw->json, ':'); |
| 129 | if (jw->pretty) |
| 130 | strbuf_addch(&jw->json, ' '); |
| 131 | } |
| 132 | |
| 133 | static void array_common(struct json_writer *jw) |
| 134 | { |
| 135 | assert_in_array(jw); |
| 136 | maybe_add_comma(jw); |
| 137 | |
| 138 | if (jw->pretty) { |
| 139 | strbuf_addch(&jw->json, '\n'); |
| 140 | indent_pretty(jw); |
| 141 | } |
| 142 | } |
| 143 | |
| 144 | /* |
| 145 | * Assert that the given JSON object or JSON array has been properly |
| 146 | * terminated. (Has closing bracket.) |
| 147 | */ |
| 148 | static void assert_is_terminated(const struct json_writer *jw) |
| 149 | { |
| 150 | if (jw->open_stack.len) |
| 151 | BUG("json-writer: object: missing jw_end(): '%s'", |
| 152 | jw->json.buf); |
| 153 | } |
| 154 | |
| 155 | void jw_object_begin(struct json_writer *jw, int pretty) |
| 156 | { |
| 157 | begin(jw, '{', pretty); |
| 158 | } |
| 159 | |
| 160 | void jw_object_string(struct json_writer *jw, const char *key, const char *value) |
| 161 | { |
| 162 | object_common(jw, key); |
| 163 | append_quoted_string(&jw->json, value); |
| 164 | } |
| 165 | |
| 166 | void jw_object_intmax(struct json_writer *jw, const char *key, intmax_t value) |
| 167 | { |
| 168 | object_common(jw, key); |
| 169 | strbuf_addf(&jw->json, "%"PRIdMAX, value); |
| 170 | } |
| 171 | |
| 172 | void jw_object_double(struct json_writer *jw, const char *key, int precision, |
| 173 | double value) |
| 174 | { |
| 175 | object_common(jw, key); |
| 176 | fmt_double(jw, precision, value); |
| 177 | } |
| 178 | |
| 179 | void jw_object_true(struct json_writer *jw, const char *key) |
| 180 | { |
| 181 | object_common(jw, key); |
| 182 | strbuf_addstr(&jw->json, "true"); |
| 183 | } |
| 184 | |
| 185 | void jw_object_false(struct json_writer *jw, const char *key) |
| 186 | { |
| 187 | object_common(jw, key); |
| 188 | strbuf_addstr(&jw->json, "false"); |
| 189 | } |
| 190 | |
| 191 | void jw_object_bool(struct json_writer *jw, const char *key, int value) |
| 192 | { |
| 193 | if (value) |
| 194 | jw_object_true(jw, key); |
| 195 | else |
| 196 | jw_object_false(jw, key); |
| 197 | } |
| 198 | |
| 199 | void jw_object_null(struct json_writer *jw, const char *key) |
| 200 | { |
| 201 | object_common(jw, key); |
| 202 | strbuf_addstr(&jw->json, "null"); |
| 203 | } |
| 204 | |
| 205 | static void increase_indent(struct strbuf *sb, |
| 206 | const struct json_writer *jw, |
| 207 | int indent) |
| 208 | { |
| 209 | int k; |
| 210 | |
| 211 | strbuf_reset(sb); |
| 212 | for (k = 0; k < jw->json.len; k++) { |
| 213 | char ch = jw->json.buf[k]; |
| 214 | strbuf_addch(sb, ch); |
| 215 | if (ch == '\n') |
| 216 | strbuf_addchars(sb, ' ', indent); |
| 217 | } |
| 218 | } |
| 219 | |
| 220 | static void kill_indent(struct strbuf *sb, |
| 221 | const struct json_writer *jw) |
| 222 | { |
| 223 | int k; |
| 224 | int eat_it = 0; |
| 225 | |
| 226 | strbuf_reset(sb); |
| 227 | for (k = 0; k < jw->json.len; k++) { |
| 228 | char ch = jw->json.buf[k]; |
| 229 | if (eat_it && ch == ' ') |
| 230 | continue; |
| 231 | if (ch == '\n') { |
| 232 | eat_it = 1; |
| 233 | continue; |
| 234 | } |
| 235 | eat_it = 0; |
| 236 | strbuf_addch(sb, ch); |
| 237 | } |
| 238 | } |
| 239 | |
| 240 | static void append_sub_jw(struct json_writer *jw, |
| 241 | const struct json_writer *value) |
| 242 | { |
| 243 | /* |
| 244 | * If both are pretty, increase the indentation of the sub_jw |
| 245 | * to better fit under the super. |
| 246 | * |
| 247 | * If the super is pretty, but the sub_jw is compact, leave the |
| 248 | * sub_jw compact. (We don't want to parse and rebuild the sub_jw |
| 249 | * for this debug-ish feature.) |
| 250 | * |
| 251 | * If the super is compact, and the sub_jw is pretty, convert |
| 252 | * the sub_jw to compact. |
| 253 | * |
| 254 | * If both are compact, keep the sub_jw compact. |
| 255 | */ |
| 256 | if (jw->pretty && jw->open_stack.len && value->pretty) { |
| 257 | struct strbuf sb = STRBUF_INIT; |
| 258 | increase_indent(&sb, value, jw->open_stack.len * 2); |
| 259 | strbuf_addbuf(&jw->json, &sb); |
| 260 | strbuf_release(&sb); |
| 261 | return; |
| 262 | } |
| 263 | if (!jw->pretty && value->pretty) { |
| 264 | struct strbuf sb = STRBUF_INIT; |
| 265 | kill_indent(&sb, value); |
| 266 | strbuf_addbuf(&jw->json, &sb); |
| 267 | strbuf_release(&sb); |
| 268 | return; |
| 269 | } |
| 270 | |
| 271 | strbuf_addbuf(&jw->json, &value->json); |
| 272 | } |
| 273 | |
| 274 | /* |
| 275 | * Append existing (properly terminated) JSON sub-data (object or array) |
| 276 | * as-is onto the given JSON data. |
| 277 | */ |
| 278 | void jw_object_sub_jw(struct json_writer *jw, const char *key, |
| 279 | const struct json_writer *value) |
| 280 | { |
| 281 | assert_is_terminated(value); |
| 282 | |
| 283 | object_common(jw, key); |
| 284 | append_sub_jw(jw, value); |
| 285 | } |
| 286 | |
| 287 | void jw_object_inline_begin_object(struct json_writer *jw, const char *key) |
| 288 | { |
| 289 | object_common(jw, key); |
| 290 | |
| 291 | jw_object_begin(jw, jw->pretty); |
| 292 | } |
| 293 | |
| 294 | void jw_object_inline_begin_array(struct json_writer *jw, const char *key) |
| 295 | { |
| 296 | object_common(jw, key); |
| 297 | |
| 298 | jw_array_begin(jw, jw->pretty); |
| 299 | } |
| 300 | |
| 301 | void jw_array_begin(struct json_writer *jw, int pretty) |
| 302 | { |
| 303 | begin(jw, '[', pretty); |
| 304 | } |
| 305 | |
| 306 | void jw_array_string(struct json_writer *jw, const char *value) |
| 307 | { |
| 308 | array_common(jw); |
| 309 | append_quoted_string(&jw->json, value); |
| 310 | } |
| 311 | |
| 312 | void jw_array_intmax(struct json_writer *jw, intmax_t value) |
| 313 | { |
| 314 | array_common(jw); |
| 315 | strbuf_addf(&jw->json, "%"PRIdMAX, value); |
| 316 | } |
| 317 | |
| 318 | void jw_array_double(struct json_writer *jw, int precision, double value) |
| 319 | { |
| 320 | array_common(jw); |
| 321 | fmt_double(jw, precision, value); |
| 322 | } |
| 323 | |
| 324 | void jw_array_true(struct json_writer *jw) |
| 325 | { |
| 326 | array_common(jw); |
| 327 | strbuf_addstr(&jw->json, "true"); |
| 328 | } |
| 329 | |
| 330 | void jw_array_false(struct json_writer *jw) |
| 331 | { |
| 332 | array_common(jw); |
| 333 | strbuf_addstr(&jw->json, "false"); |
| 334 | } |
| 335 | |
| 336 | void jw_array_bool(struct json_writer *jw, int value) |
| 337 | { |
| 338 | if (value) |
| 339 | jw_array_true(jw); |
| 340 | else |
| 341 | jw_array_false(jw); |
| 342 | } |
| 343 | |
| 344 | void jw_array_null(struct json_writer *jw) |
| 345 | { |
| 346 | array_common(jw); |
| 347 | strbuf_addstr(&jw->json, "null"); |
| 348 | } |
| 349 | |
| 350 | void jw_array_sub_jw(struct json_writer *jw, const struct json_writer *value) |
| 351 | { |
| 352 | assert_is_terminated(value); |
| 353 | |
| 354 | array_common(jw); |
| 355 | append_sub_jw(jw, value); |
| 356 | } |
| 357 | |
| 358 | void jw_array_argc_argv(struct json_writer *jw, int argc, const char **argv) |
| 359 | { |
| 360 | int k; |
| 361 | |
| 362 | for (k = 0; k < argc; k++) |
| 363 | jw_array_string(jw, argv[k]); |
| 364 | } |
| 365 | |
| 366 | void jw_array_argv(struct json_writer *jw, const char **argv) |
| 367 | { |
| 368 | while (*argv) |
| 369 | jw_array_string(jw, *argv++); |
| 370 | } |
| 371 | |
| 372 | void jw_array_inline_begin_object(struct json_writer *jw) |
| 373 | { |
| 374 | array_common(jw); |
| 375 | |
| 376 | jw_object_begin(jw, jw->pretty); |
| 377 | } |
| 378 | |
| 379 | void jw_array_inline_begin_array(struct json_writer *jw) |
| 380 | { |
| 381 | array_common(jw); |
| 382 | |
| 383 | jw_array_begin(jw, jw->pretty); |
| 384 | } |
| 385 | |
| 386 | int jw_is_terminated(const struct json_writer *jw) |
| 387 | { |
| 388 | return !jw->open_stack.len; |
| 389 | } |
| 390 | |
| 391 | void jw_end(struct json_writer *jw) |
| 392 | { |
| 393 | char ch_open; |
| 394 | int len; |
| 395 | |
| 396 | if (!jw->open_stack.len) |
| 397 | BUG("json-writer: too many jw_end(): '%s'", jw->json.buf); |
| 398 | |
| 399 | len = jw->open_stack.len - 1; |
| 400 | ch_open = jw->open_stack.buf[len]; |
| 401 | |
| 402 | strbuf_setlen(&jw->open_stack, len); |
| 403 | jw->need_comma = 1; |
| 404 | |
| 405 | if (jw->pretty) { |
| 406 | strbuf_addch(&jw->json, '\n'); |
| 407 | indent_pretty(jw); |
| 408 | } |
| 409 | |
| 410 | if (ch_open == '{') |
| 411 | strbuf_addch(&jw->json, '}'); |
| 412 | else |
| 413 | strbuf_addch(&jw->json, ']'); |
| 414 | } |