/* Spa * Copyright (C) 2017 Wim Taymans * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Library General Public * License as published by the Free Software Foundation; either * version 2 of the License, or (at your option) any later version. * * This library 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 * Library General Public License for more details. * * You should have received a copy of the GNU Library General Public * License along with this library; if not, write to the * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, * Boston, MA 02110-1301, USA. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #if 0 /* * JSON based format description [ , [ , ], { : , ... } ] = [ , , [ ,... ]] | = "123.." 1: s = string : "value" i = int : l = long : f = float : d = double : b = bool : true | false R = rectangle : [ , ] F = fraction : [ , ] 2: - = default (only default value present) e = enum : [ , ... ] f = flags : [ ] r = min/max : [ , ] s = min/max/step : [ , , ] 3: u = unset : value is unset, choose from options or default o = optional : value does not need to be set r = readonly : value is read only d = deprecated : value is deprecated [ "Format", [ "video", "raw"], { "format" : [ "se", "I420", [ "I420", "YUY2" ] ], "size" : [ "Rru", [320, 240], [[ 640, 480], [1024,786]]], "framerate" : [ "Fsu", [25, 1], [[ 0, 1], [65536,1]]]" } ] [ "Format", [ "audio", "raw"], { "format" : [ "se", "S16LE", [ "F32LE", "S16LE" ] ], "rate" : [ "iru", 44100, [8000, 96000]], "channels" : [ "iru", 1, [1, 4096]]" "interleaved" : [ "beo", true ]" } ] */ #endif #include #define STRUCT 0 #define BARE 1 #define STRING 2 #define UTF8 3 #define ESC 4 struct spa_json_iter { const char *start; const char *cur; const char *end; int state; int depth; }; struct spa_json_chunk { const char *value; int len; }; static inline int spa_json_chunk_extract(struct spa_json_chunk *chunk, const char *template, ...); enum spa_json_type { SPA_JSON_TYPE_ANY = '-', SPA_JSON_TYPE_CHUNK = 'c', SPA_JSON_TYPE_INT = 'i', SPA_JSON_TYPE_LONG = 'l', SPA_JSON_TYPE_FLOAT = 'f', SPA_JSON_TYPE_DOUBLE = 'd', SPA_JSON_TYPE_STRING = 's', SPA_JSON_TYPE_BOOL = 'b', SPA_JSON_TYPE_RECTANGLE = 'R', SPA_JSON_TYPE_FRACTION = 'F', SPA_JSON_TYPE_OBJECT = 'o', SPA_JSON_TYPE_ARRAY = 'a' }; static inline bool spa_json_chunk_is_type(struct spa_json_chunk *chunk, enum spa_json_type type) { switch (type) { case SPA_JSON_TYPE_ANY: case SPA_JSON_TYPE_CHUNK: return true; case SPA_JSON_TYPE_INT: case SPA_JSON_TYPE_LONG: case SPA_JSON_TYPE_FLOAT: case SPA_JSON_TYPE_DOUBLE: return (chunk->value[0] >= '0' && chunk->value[0] <= '9') || chunk->value[0] == '-' ; case SPA_JSON_TYPE_STRING: return chunk->value[0] == '\"'; case SPA_JSON_TYPE_BOOL: return chunk->value[0] == 't' || chunk->value[0] == 'f'; case SPA_JSON_TYPE_RECTANGLE: case SPA_JSON_TYPE_FRACTION: case SPA_JSON_TYPE_ARRAY: return chunk->value[0] == '['; case SPA_JSON_TYPE_OBJECT: return chunk->value[0] == '{'; } return false; } static inline int spa_json_chunk_to_int(struct spa_json_chunk *chunk) { return atoi(chunk->value); } static inline int64_t spa_json_chunk_to_long(struct spa_json_chunk *chunk) { return atol(chunk->value); } static inline int64_t spa_json_chunk_to_float(struct spa_json_chunk *chunk) { return strtof(chunk->value, NULL); } static inline int64_t spa_json_chunk_to_double(struct spa_json_chunk *chunk) { return strtod(chunk->value, NULL); } static inline bool spa_json_chunk_to_bool(struct spa_json_chunk *chunk) { return chunk->value[0] == 't'; } static inline int spa_json_chunk_to_rectangle(struct spa_json_chunk *chunk, struct spa_rectangle *rect) { return spa_json_chunk_extract(chunk, "[ #pi, #pi ]", &rect->width, &rect->height); } static inline int spa_json_chunk_to_fraction(struct spa_json_chunk *chunk, struct spa_fraction *frac) { return spa_json_chunk_extract(chunk, "[ #pi, #pi ]", &frac->num, &frac->denom); } static inline void spa_json_iter_init (struct spa_json_iter *iter, const char *data, size_t size) { iter->start = iter->cur = data; iter->end = size == -1 ? NULL : data + size; iter->state = STRUCT; iter->depth = 0; } static inline bool spa_json_iter_chunk(struct spa_json_iter *iter, struct spa_json_chunk *chunk) { if (!spa_json_chunk_is_type(chunk, SPA_JSON_TYPE_OBJECT) && !spa_json_chunk_is_type(chunk, SPA_JSON_TYPE_ARRAY)) return false; spa_json_iter_init (iter, chunk->value, -1); iter->cur++; return true; } static inline int spa_json_iter_next_chunk(struct spa_json_iter *iter, struct spa_json_chunk *chunk) { int utf8_remain = 0; for (;iter->end == NULL || iter->cur < iter->end; iter->cur++) { unsigned char cur = (unsigned char) *iter->cur; again: switch (iter->state) { case STRUCT: switch (cur) { case '\t': case ' ': case '\r': case '\n': case ':': case ',': continue; case '"': chunk->value = iter->cur; iter->state = STRING; continue; case '[': case '{': chunk->value = iter->cur; if (++iter->depth > 1) continue; iter->cur++; return chunk->len = 1; case '}': case ']': if (iter->depth == 0) return 0; --iter->depth; continue; case '-': case 'a' ... 'z': case 'A' ... 'Z': case '0' ... '9': case '#': chunk->value = iter->cur; iter->state = BARE; continue; case '\0': return 0; } return -1; case BARE: switch (cur) { case '\t': case ' ': case '\r': case '\n': case ':': case ',': case ']': case '}': iter->state = STRUCT; if (iter->depth > 0) goto again; return chunk->len = iter->cur - chunk->value; default: if (cur >= 32 && cur <= 126) continue; } return -1; case STRING: switch (cur) { case '\\': iter->state = ESC; continue; case '"': iter->state = STRUCT; if (iter->depth > 0) continue; iter->cur++; return chunk->len = iter->cur - chunk->value; case 240 ... 247: utf8_remain++; case 224 ... 239: utf8_remain++; case 192 ... 223: utf8_remain++; iter->state = UTF8; continue; default: if (cur >= 32 && cur <= 126) continue; } return -1; case UTF8: switch (cur) { case 128 ... 191: if (--utf8_remain == 0) iter->state = STRING; continue; } return -1; case ESC: switch (cur) { case '"': case '\\': case '/': case 'b': case 'f': case 'n': case 'r': case 't': case 'u': iter->state = STRING; continue; } return -1; } } return iter->depth == 0 ? 0 : -1; } static inline void spa_json_chunk_print(struct spa_json_chunk *chunk, int prefix) { struct spa_json_iter iter; if (spa_json_iter_chunk(&iter, chunk)) { struct spa_json_chunk chunk2 = { NULL, }; printf ("%-*s%c\n", prefix, "", chunk->value[0]); while (spa_json_iter_next_chunk(&iter, &chunk2) > 0) spa_json_chunk_print(&chunk2, prefix + 2); printf ("%-*s%c\n", prefix, "", iter.cur[0]); } else { printf ("%-*s%.*s\n", prefix, "", chunk->len, chunk->value); } } static inline int spa_json_iter_find_key(struct spa_json_iter *iter, const char *key) { struct spa_json_chunk ch = { NULL, }; int res; iter->cur = iter->start + 1; iter->depth = 0; iter->state = STRUCT; while (true) { /* read key */ if ((res = spa_json_iter_next_chunk(iter, &ch)) <= 0) return res; if (spa_json_chunk_is_type(&ch, SPA_JSON_TYPE_STRING) && strncmp(key, ch.value, ch.len) == 0) return 1; } return 0; } enum spa_json_prop_range { SPA_JSON_PROP_RANGE_NONE = '-', SPA_JSON_PROP_RANGE_MIN_MAX = 'r', SPA_JSON_PROP_RANGE_STEP = 's', SPA_JSON_PROP_RANGE_ENUM = 'e', SPA_JSON_PROP_RANGE_FLAGS = 'f' }; enum spa_json_prop_flags { SPA_JSON_PROP_FLAG_UNSET = (1 << 0), SPA_JSON_PROP_FLAG_OPTIONAL = (1 << 1), SPA_JSON_PROP_FLAG_READONLY = (1 << 2), SPA_JSON_PROP_FLAG_DEPRECATED = (1 << 3), }; struct spa_json_prop { enum spa_json_type type; enum spa_json_prop_range range; enum spa_json_prop_flags flags; struct spa_json_chunk value; struct spa_json_chunk alternatives; }; static inline int spa_json_chunk_parse_prop(struct spa_json_chunk *chunk, char type, struct spa_json_prop *prop) { if (spa_json_chunk_is_type(chunk, SPA_JSON_TYPE_ARRAY)) { struct spa_json_chunk flags; int res; char ch; /* [, , [,...]] */ if ((res = spa_json_chunk_extract(chunk, "[ #&cs, #&c-, #&ca ]", &flags, &prop->value, &prop->alternatives)) < 3) { printf("can't parse prop chunk %d\n", res); return -1; } /* skip \" */ flags.value++; prop->type = *flags.value++; if (type != SPA_JSON_TYPE_ANY && type != SPA_JSON_TYPE_CHUNK && prop->type != type) { printf("prop chunk of wrong type %d %d\n", prop->type, type); return -1; } prop->range = *flags.value++; /* flags */ prop->flags = 0; while ((ch = *flags.value++) != '\"') { switch (ch) { case 'u': prop->flags |= SPA_JSON_PROP_FLAG_UNSET; break; case 'o': prop->flags |= SPA_JSON_PROP_FLAG_OPTIONAL; break; case 'r': prop->flags |= SPA_JSON_PROP_FLAG_READONLY; break; case 'd': prop->flags |= SPA_JSON_PROP_FLAG_DEPRECATED; break; } } } else { /* */ prop->type = type; prop->range = SPA_JSON_PROP_RANGE_NONE; prop->flags = 0; prop->value = *chunk; prop->alternatives = *chunk; } return 0; } /** * #[*] * * * = skip assignment * is: * & -> pointer to type * p -> property, fixed value store in pointer to type * P -> property, stored in pointer to struct spa_json_prop * * * - -> any * c -> store as chunk if of type * s -> string * i -> int * l -> long * f -> float * d -> double * b -> bool * R -> rectangle * F -> fraction * a -> array * o -> object */ static inline int spa_json_chunk_extract(struct spa_json_chunk *chunk, const char *template, ...) { struct spa_json_iter templ[16], it[16]; struct spa_json_chunk tch = { NULL, }, ch = { NULL, }; struct spa_json_prop prop; const char *match; int collected = 0, res, level = 0; va_list args; bool store; va_start(args, template); spa_json_iter_init(&it[0], chunk->value, chunk->len); spa_json_iter_init (&templ[0], template, -1); while (true) { res = spa_json_iter_next_chunk(&templ[level], &tch); if (res == 0) { if (--level == 0) break; continue; } else if (res < 0) { return res; } switch (tch.value[0]) { case '[': case '{': if (spa_json_iter_next_chunk(&it[level], &ch) <= 0 || ch.value[0] != tch.value[0]) return -1; if (++level == 16) return -2; spa_json_iter_chunk(&it[level], &ch); spa_json_iter_chunk(&templ[level], &tch); break; case '"': case '-': case '0' ... '9': case 't': case 'f': case 'n': if (templ[level].start[0] == '{') { if (spa_json_iter_find_key(&it[level], tch.value) <= 0) continue; } else if (spa_json_iter_next_chunk(&it[level], &ch) <= 0 || ch.len != tch.len || strncmp(ch.value, tch.value, ch.len) != 0) return -1; break; case '#': match = tch.value + 1; if (spa_json_iter_next_chunk(&it[level], &ch) <= 0) return -1; store = (match[0] != '*'); if (!store) match++; switch (match[0]) { case 'p': case 'P': if (spa_json_chunk_parse_prop(&ch, match[1], &prop) < 0) goto skip; if (match[0] == 'P') { if (store) *va_arg(args, struct spa_json_prop *) = prop; collected++; break; } else { if (prop.flags & SPA_JSON_PROP_FLAG_UNSET) goto skip; ch = prop.value; } /* fallthrough */ case '&': if (!spa_json_chunk_is_type(&ch, match[1] == SPA_JSON_TYPE_CHUNK ? match[2] : match[1])) { skip: if (store) va_arg(args, void *); break; } if (!store) break; collected++; switch (match[1]) { case SPA_JSON_TYPE_CHUNK: *va_arg(args, struct spa_json_chunk *) = ch; break; case SPA_JSON_TYPE_INT: *va_arg(args, int *) = spa_json_chunk_to_int(&ch); break; case SPA_JSON_TYPE_LONG: *va_arg(args, int64_t *) = spa_json_chunk_to_long(&ch); break; case SPA_JSON_TYPE_FLOAT: *va_arg(args, float *) = spa_json_chunk_to_float(&ch); break; case SPA_JSON_TYPE_DOUBLE: *va_arg(args, double *) = spa_json_chunk_to_double(&ch); break; case SPA_JSON_TYPE_BOOL: *va_arg(args, bool *) = spa_json_chunk_to_bool(&ch); break; case SPA_JSON_TYPE_RECTANGLE: spa_json_chunk_to_rectangle(&ch, va_arg(args, struct spa_rectangle *)); break; case SPA_JSON_TYPE_FRACTION: spa_json_chunk_to_fraction(&ch, va_arg(args, struct spa_fraction *)); break; default: printf("ignoring invalid #p type %c\n", match[1]); va_arg(args, void *); collected--; continue; } break; default: printf("ignoring unknown match type %c\n", *match); break; } break; default: printf("invalid char %c\n", tch.value[0]); return -2; } } va_end(args); return collected; } static int spa_json_iter_array(struct spa_json_iter *iter, struct spa_json_iter *array) { struct spa_json_chunk chunk = { NULL, }; if (spa_json_iter_next_chunk(iter, &chunk) <= 0 || !spa_json_chunk_is_type(&chunk, SPA_JSON_TYPE_ARRAY)) return -1; return spa_json_iter_chunk(array, &chunk); } static int spa_json_iter_object(struct spa_json_iter *iter, struct spa_json_iter *object) { struct spa_json_chunk chunk; if (spa_json_iter_next_chunk(iter, &chunk) <= 0 || !spa_json_chunk_is_type(&chunk, SPA_JSON_TYPE_OBJECT)) return -1; return spa_json_iter_chunk(object, &chunk); } static int spa_json_iter_string(struct spa_json_iter *iter, struct spa_json_chunk *str) { if (spa_json_iter_next_chunk(iter, str) <= 0) return -1; return spa_json_chunk_is_type(str, SPA_JSON_TYPE_STRING) ? 0 : -1; } static int spa_format_parse(struct spa_json_iter *iter, struct spa_json_chunk *media_type, struct spa_json_chunk *media_subtype, struct spa_json_iter *props) { struct spa_json_iter it[2]; struct spa_json_chunk type; if (spa_json_iter_array(iter, &it[0]) < 0) return -1; if (spa_json_iter_string(&it[0], &type) < 0) return -1; if (strncmp(type.value, "\"Format\"", type.len) != 0) return -1; if (spa_json_iter_array(&it[0], &it[1]) < 0) return -1; if (spa_json_iter_string(&it[1], media_type) < 0) return -1; if (spa_json_iter_string(&it[1], media_subtype) < 0) return -1; return spa_json_iter_object(&it[0], props); } static int test_parsing(const char *format) { struct spa_json_iter iter[5]; struct spa_json_chunk media_type, media_subtype, value = { NULL, }; struct spa_json_iter props; spa_json_iter_init (&iter[0], format, strlen(format)); if (spa_format_parse(&iter[0], &media_type, &media_subtype, &props) < 0) return -1; printf("Media Type: %.*s\n", media_type.len, media_type.value); printf("Media SubType: %.*s\n", media_subtype.len, media_subtype.value); while (spa_json_iter_string(&props, &value) >= 0) { printf("Key: %.*s\n", value.len, value.value); if (spa_json_iter_array(&props, &iter[1]) < 0) return -1; if (spa_json_iter_string(&iter[1], &value) < 0) return -1; printf("flags: %.*s\n", value.len, value.value); if (spa_json_iter_next_chunk(&iter[1], &value) <= 0) return -1; printf("default: %.*s\n", value.len, value.value); if (spa_json_iter_array(&iter[1], &iter[2]) < 0) return -1; while (spa_json_iter_next_chunk(&iter[2], &value) > 0) { printf("value: %.*s\n", value.len, value.value); } } return 0; } static int test_extract(const char *fmt) { struct spa_json_iter iter; struct spa_json_chunk chunk; struct spa_json_chunk media_type; struct spa_json_chunk media_subtype; struct spa_json_chunk format_flags; struct spa_json_chunk format; struct spa_json_chunk rate; struct spa_json_prop channels; int res; spa_json_iter_init (&iter, fmt, strlen(fmt)); spa_json_iter_next_chunk(&iter, &chunk); res = spa_json_chunk_extract(&chunk, "[ \"Format\", " " [ #&cs, #&cs], " " { " " \"rate\": #&c-, " " \"format\": [ #&cs, #&c-, #*&ca ], " " \"channels\": #P-" " } " "]", &media_type, &media_subtype, &rate, &format_flags, &format, &channels); printf("collected %d\n", res); printf("media type %.*s\n", media_type.len, media_type.value); printf("media subtype %.*s\n", media_subtype.len, media_subtype.value); printf("rate: %.*s\n", rate.len, rate.value); spa_json_chunk_print(&rate, 4); printf("format flags:\n"); spa_json_chunk_print(&format_flags, 4); printf("format default:\n"); spa_json_chunk_print(&format, 4); printf("channels prop %c %c %04x:\n", channels.type, channels.range, channels.flags); printf("channels value:\n"); spa_json_chunk_print(&channels.value, 4); printf("channels alt:\n"); spa_json_chunk_print(&channels.alternatives, 4); return 0; } static int test_extract2(const char *fmt) { struct spa_json_iter iter; struct spa_json_chunk chunk; struct spa_json_chunk media_type; struct spa_json_chunk media_subtype; struct spa_json_chunk props, rate, format; int res; spa_json_iter_init (&iter, fmt, strlen(fmt)); spa_json_iter_next_chunk(&iter, &chunk); res = spa_json_chunk_extract(&chunk, "[ \"Format\", " " [ #&cs, #&cs], " " #&c- " "]", &media_type, &media_subtype, &props); printf("collected %d\n", res); printf("media type %.*s\n", media_type.len, media_type.value); printf("media subtype %.*s\n", media_subtype.len, media_subtype.value); printf("props:\n"); spa_json_iter_chunk(&iter, &props); printf("rate:\n"); if (spa_json_iter_find_key(&iter, "\"rate\"") > 0) { spa_json_iter_next_chunk(&iter, &rate); spa_json_chunk_print(&rate, 4); } printf("format:\n"); if (spa_json_iter_find_key(&iter, "\"format\"") > 0) { spa_json_iter_next_chunk(&iter, &format); spa_json_chunk_print(&format, 4); } return 0; } static int test_extract3(const char *fmt) { struct spa_json_iter iter; struct spa_json_chunk chunk; struct spa_json_chunk media_type; struct spa_json_chunk media_subtype; struct spa_json_chunk format; int rate = -1, res; struct spa_json_prop channels; spa_json_iter_init (&iter, fmt, strlen(fmt)); spa_json_iter_next_chunk(&iter, &chunk); res = spa_json_chunk_extract(&chunk, "[ \"Format\", " " [ #&cs, #&cs], " " { " " \"rate\": #pi, " " \"format\": #pcs, " " \"channels\": #P-" " } " "]", &media_type, &media_subtype, &rate, &format, &channels); printf("collected %d\n", res); printf("media type %.*s\n", media_type.len, media_type.value); printf("media subtype %.*s\n", media_subtype.len, media_subtype.value); printf("media rate %d\n", rate); printf("media format %.*s\n", format.len, format.value); printf("media channels: %c %c %04x\n",channels.type, channels.range, channels.flags); spa_json_chunk_print(&channels.value, 2); spa_json_chunk_print(&channels.alternatives, 2); return 0; } int main(int argc, char *argv[]) { struct spa_json_iter iter; struct spa_json_chunk chunk; const char *format = "[ \"Format\", " " [ \"audio\", \"raw\"], " " { " " \"format\": [ \"se\", \"S16LE\", [ \"F32LE\", \"S16LE\" ]], " " \"rate\": [ \"iru\", 44100, [8000, 96000]]," " \"channels\": [ \"iru\", 1, [1, 4096]]" " \"interleaved\": [ \"beo\", true ]" " }" "]"; spa_json_iter_init(&iter, format, -1); spa_json_iter_next_chunk(&iter, &chunk); spa_json_chunk_print(&chunk, 0); test_parsing(format); test_extract(format); test_extract2(format); test_extract3(format); test_extract3( "[ \"Format\", " " [ \"audio\", \"raw\"], " " { " " \"format\": \"S16LE\", " " \"rate\": 44100, " " \"channels\": 2, " " }" "]"); return 0; }