diff options
Diffstat (limited to 'qemu/qobject/json-parser.c')
-rw-r--r-- | qemu/qobject/json-parser.c | 340 |
1 files changed, 103 insertions, 237 deletions
diff --git a/qemu/qobject/json-parser.c b/qemu/qobject/json-parser.c index ac991ba3c..67ed72731 100644 --- a/qemu/qobject/json-parser.c +++ b/qemu/qobject/json-parser.c @@ -1,5 +1,5 @@ /* - * JSON Parser + * JSON Parser * * Copyright IBM, Corp. 2009 * @@ -11,8 +11,8 @@ * */ -#include <stdarg.h> - +#include "qemu/osdep.h" +#include "qapi/error.h" #include "qemu-common.h" #include "qapi/qmp/qstring.h" #include "qapi/qmp/qint.h" @@ -22,15 +22,13 @@ #include "qapi/qmp/qbool.h" #include "qapi/qmp/json-parser.h" #include "qapi/qmp/json-lexer.h" +#include "qapi/qmp/json-streamer.h" typedef struct JSONParserContext { Error *err; - struct { - QObject **buf; - size_t pos; - size_t count; - } tokens; + JSONToken *current; + GQueue *buf; } JSONParserContext; #define BUG_ON(cond) assert(!(cond)) @@ -47,58 +45,10 @@ typedef struct JSONParserContext static QObject *parse_value(JSONParserContext *ctxt, va_list *ap); /** - * Token manipulators - * - * tokens are dictionaries that contain a type, a string value, and geometry information - * about a token identified by the lexer. These are routines that make working with - * these objects a bit easier. - */ -static const char *token_get_value(QObject *obj) -{ - return qdict_get_str(qobject_to_qdict(obj), "token"); -} - -static JSONTokenType token_get_type(QObject *obj) -{ - return qdict_get_int(qobject_to_qdict(obj), "type"); -} - -static int token_is_operator(QObject *obj, char op) -{ - const char *val; - - if (token_get_type(obj) != JSON_OPERATOR) { - return 0; - } - - val = token_get_value(obj); - - return (val[0] == op) && (val[1] == 0); -} - -static int token_is_keyword(QObject *obj, const char *value) -{ - if (token_get_type(obj) != JSON_KEYWORD) { - return 0; - } - - return strcmp(token_get_value(obj), value) == 0; -} - -static int token_is_escape(QObject *obj, const char *value) -{ - if (token_get_type(obj) != JSON_ESCAPE) { - return 0; - } - - return (strcmp(token_get_value(obj), value) == 0); -} - -/** * Error handler */ static void GCC_FMT_ATTR(3, 4) parse_error(JSONParserContext *ctxt, - QObject *token, const char *msg, ...) + JSONToken *token, const char *msg, ...) { va_list ap; char message[1024]; @@ -176,9 +126,10 @@ static int hex2decimal(char ch) * \t * \u four-hex-digits */ -static QString *qstring_from_escaped_str(JSONParserContext *ctxt, QObject *token) +static QString *qstring_from_escaped_str(JSONParserContext *ctxt, + JSONToken *token) { - const char *ptr = token_get_value(token); + const char *ptr = token->str; QString *str; int double_quote = 1; @@ -274,73 +225,34 @@ out: return NULL; } -static QObject *parser_context_pop_token(JSONParserContext *ctxt) -{ - QObject *token; - g_assert(ctxt->tokens.pos < ctxt->tokens.count); - token = ctxt->tokens.buf[ctxt->tokens.pos]; - ctxt->tokens.pos++; - return token; -} - -/* Note: parser_context_{peek|pop}_token do not increment the - * token object's refcount. In both cases the references will continue - * to be tracked and cleaned up in parser_context_free(), so do not - * attempt to free the token object. +/* Note: the token object returned by parser_context_peek_token or + * parser_context_pop_token is deleted as soon as parser_context_pop_token + * is called again. */ -static QObject *parser_context_peek_token(JSONParserContext *ctxt) -{ - QObject *token; - g_assert(ctxt->tokens.pos < ctxt->tokens.count); - token = ctxt->tokens.buf[ctxt->tokens.pos]; - return token; -} - -static JSONParserContext parser_context_save(JSONParserContext *ctxt) -{ - JSONParserContext saved_ctxt = {0}; - saved_ctxt.tokens.pos = ctxt->tokens.pos; - saved_ctxt.tokens.count = ctxt->tokens.count; - saved_ctxt.tokens.buf = ctxt->tokens.buf; - return saved_ctxt; -} - -static void parser_context_restore(JSONParserContext *ctxt, - JSONParserContext saved_ctxt) +static JSONToken *parser_context_pop_token(JSONParserContext *ctxt) { - ctxt->tokens.pos = saved_ctxt.tokens.pos; - ctxt->tokens.count = saved_ctxt.tokens.count; - ctxt->tokens.buf = saved_ctxt.tokens.buf; + g_free(ctxt->current); + assert(!g_queue_is_empty(ctxt->buf)); + ctxt->current = g_queue_pop_head(ctxt->buf); + return ctxt->current; } -static void tokens_append_from_iter(QObject *obj, void *opaque) +static JSONToken *parser_context_peek_token(JSONParserContext *ctxt) { - JSONParserContext *ctxt = opaque; - g_assert(ctxt->tokens.pos < ctxt->tokens.count); - ctxt->tokens.buf[ctxt->tokens.pos++] = obj; - qobject_incref(obj); + assert(!g_queue_is_empty(ctxt->buf)); + return g_queue_peek_head(ctxt->buf); } -static JSONParserContext *parser_context_new(QList *tokens) +static JSONParserContext *parser_context_new(GQueue *tokens) { JSONParserContext *ctxt; - size_t count; if (!tokens) { return NULL; } - count = qlist_size(tokens); - if (count == 0) { - return NULL; - } - ctxt = g_malloc0(sizeof(JSONParserContext)); - ctxt->tokens.pos = 0; - ctxt->tokens.count = count; - ctxt->tokens.buf = g_malloc(count * sizeof(QObject *)); - qlist_iter(tokens, tokens_append_from_iter, ctxt); - ctxt->tokens.pos = 0; + ctxt->buf = tokens; return ctxt; } @@ -348,12 +260,12 @@ static JSONParserContext *parser_context_new(QList *tokens) /* to support error propagation, ctxt->err must be freed separately */ static void parser_context_free(JSONParserContext *ctxt) { - int i; if (ctxt) { - for (i = 0; i < ctxt->tokens.count; i++) { - qobject_decref(ctxt->tokens.buf[i]); + while (!g_queue_is_empty(ctxt->buf)) { + parser_context_pop_token(ctxt); } - g_free(ctxt->tokens.buf); + g_free(ctxt->current); + g_queue_free(ctxt->buf); g_free(ctxt); } } @@ -363,8 +275,8 @@ static void parser_context_free(JSONParserContext *ctxt) */ static int parse_pair(JSONParserContext *ctxt, QDict *dict, va_list *ap) { - QObject *key = NULL, *token = NULL, *value, *peek; - JSONParserContext saved_ctxt = parser_context_save(ctxt); + QObject *key = NULL, *value; + JSONToken *peek, *token; peek = parser_context_peek_token(ctxt); if (peek == NULL) { @@ -384,7 +296,7 @@ static int parse_pair(JSONParserContext *ctxt, QDict *dict, va_list *ap) goto out; } - if (!token_is_operator(token, ':')) { + if (token->type != JSON_COLON) { parse_error(ctxt, token, "missing : in object pair"); goto out; } @@ -402,7 +314,6 @@ static int parse_pair(JSONParserContext *ctxt, QDict *dict, va_list *ap) return 0; out: - parser_context_restore(ctxt, saved_ctxt); qobject_decref(key); return -1; @@ -411,17 +322,10 @@ out: static QObject *parse_object(JSONParserContext *ctxt, va_list *ap) { QDict *dict = NULL; - QObject *token, *peek; - JSONParserContext saved_ctxt = parser_context_save(ctxt); + JSONToken *token, *peek; token = parser_context_pop_token(ctxt); - if (token == NULL) { - goto out; - } - - if (!token_is_operator(token, '{')) { - goto out; - } + assert(token && token->type == JSON_LCURLY); dict = qdict_new(); @@ -431,7 +335,7 @@ static QObject *parse_object(JSONParserContext *ctxt, va_list *ap) goto out; } - if (!token_is_operator(peek, '}')) { + if (peek->type != JSON_RCURLY) { if (parse_pair(ctxt, dict, ap) == -1) { goto out; } @@ -442,8 +346,8 @@ static QObject *parse_object(JSONParserContext *ctxt, va_list *ap) goto out; } - while (!token_is_operator(token, '}')) { - if (!token_is_operator(token, ',')) { + while (token->type != JSON_RCURLY) { + if (token->type != JSON_COMMA) { parse_error(ctxt, token, "expected separator in dict"); goto out; } @@ -465,7 +369,6 @@ static QObject *parse_object(JSONParserContext *ctxt, va_list *ap) return QOBJECT(dict); out: - parser_context_restore(ctxt, saved_ctxt); QDECREF(dict); return NULL; } @@ -473,17 +376,10 @@ out: static QObject *parse_array(JSONParserContext *ctxt, va_list *ap) { QList *list = NULL; - QObject *token, *peek; - JSONParserContext saved_ctxt = parser_context_save(ctxt); + JSONToken *token, *peek; token = parser_context_pop_token(ctxt); - if (token == NULL) { - goto out; - } - - if (!token_is_operator(token, '[')) { - goto out; - } + assert(token && token->type == JSON_LSQUARE); list = qlist_new(); @@ -493,7 +389,7 @@ static QObject *parse_array(JSONParserContext *ctxt, va_list *ap) goto out; } - if (!token_is_operator(peek, ']')) { + if (peek->type != JSON_RSQUARE) { QObject *obj; obj = parse_value(ctxt, ap); @@ -510,8 +406,8 @@ static QObject *parse_array(JSONParserContext *ctxt, va_list *ap) goto out; } - while (!token_is_operator(token, ']')) { - if (!token_is_operator(token, ',')) { + while (token->type != JSON_RSQUARE) { + if (token->type != JSON_COMMA) { parse_error(ctxt, token, "expected separator in list"); goto out; } @@ -537,99 +433,68 @@ static QObject *parse_array(JSONParserContext *ctxt, va_list *ap) return QOBJECT(list); out: - parser_context_restore(ctxt, saved_ctxt); QDECREF(list); return NULL; } static QObject *parse_keyword(JSONParserContext *ctxt) { - QObject *token, *ret; - JSONParserContext saved_ctxt = parser_context_save(ctxt); + JSONToken *token; token = parser_context_pop_token(ctxt); - if (token == NULL) { - goto out; - } - - if (token_get_type(token) != JSON_KEYWORD) { - goto out; - } + assert(token && token->type == JSON_KEYWORD); - if (token_is_keyword(token, "true")) { - ret = QOBJECT(qbool_from_bool(true)); - } else if (token_is_keyword(token, "false")) { - ret = QOBJECT(qbool_from_bool(false)); - } else if (token_is_keyword(token, "null")) { - ret = qnull(); - } else { - parse_error(ctxt, token, "invalid keyword `%s'", token_get_value(token)); - goto out; + if (!strcmp(token->str, "true")) { + return QOBJECT(qbool_from_bool(true)); + } else if (!strcmp(token->str, "false")) { + return QOBJECT(qbool_from_bool(false)); + } else if (!strcmp(token->str, "null")) { + return qnull(); } - - return ret; - -out: - parser_context_restore(ctxt, saved_ctxt); - + parse_error(ctxt, token, "invalid keyword '%s'", token->str); return NULL; } static QObject *parse_escape(JSONParserContext *ctxt, va_list *ap) { - QObject *token = NULL, *obj; - JSONParserContext saved_ctxt = parser_context_save(ctxt); + JSONToken *token; if (ap == NULL) { - goto out; + return NULL; } token = parser_context_pop_token(ctxt); - if (token == NULL) { - goto out; - } - - if (token_is_escape(token, "%p")) { - obj = va_arg(*ap, QObject *); - } else if (token_is_escape(token, "%i")) { - obj = QOBJECT(qbool_from_bool(va_arg(*ap, int))); - } else if (token_is_escape(token, "%d")) { - obj = QOBJECT(qint_from_int(va_arg(*ap, int))); - } else if (token_is_escape(token, "%ld")) { - obj = QOBJECT(qint_from_int(va_arg(*ap, long))); - } else if (token_is_escape(token, "%lld") || - token_is_escape(token, "%I64d")) { - obj = QOBJECT(qint_from_int(va_arg(*ap, long long))); - } else if (token_is_escape(token, "%s")) { - obj = QOBJECT(qstring_from_str(va_arg(*ap, const char *))); - } else if (token_is_escape(token, "%f")) { - obj = QOBJECT(qfloat_from_double(va_arg(*ap, double))); - } else { - goto out; + assert(token && token->type == JSON_ESCAPE); + + if (!strcmp(token->str, "%p")) { + return va_arg(*ap, QObject *); + } else if (!strcmp(token->str, "%i")) { + return QOBJECT(qbool_from_bool(va_arg(*ap, int))); + } else if (!strcmp(token->str, "%d")) { + return QOBJECT(qint_from_int(va_arg(*ap, int))); + } else if (!strcmp(token->str, "%ld")) { + return QOBJECT(qint_from_int(va_arg(*ap, long))); + } else if (!strcmp(token->str, "%lld") || + !strcmp(token->str, "%I64d")) { + return QOBJECT(qint_from_int(va_arg(*ap, long long))); + } else if (!strcmp(token->str, "%s")) { + return QOBJECT(qstring_from_str(va_arg(*ap, const char *))); + } else if (!strcmp(token->str, "%f")) { + return QOBJECT(qfloat_from_double(va_arg(*ap, double))); } - - return obj; - -out: - parser_context_restore(ctxt, saved_ctxt); - return NULL; } static QObject *parse_literal(JSONParserContext *ctxt) { - QObject *token, *obj; - JSONParserContext saved_ctxt = parser_context_save(ctxt); + JSONToken *token; token = parser_context_pop_token(ctxt); - if (token == NULL) { - goto out; - } + assert(token); - switch (token_get_type(token)) { + switch (token->type) { case JSON_STRING: - obj = QOBJECT(qstring_from_escaped_str(ctxt, token)); - break; + return QOBJECT(qstring_from_escaped_str(ctxt, token)); case JSON_INTEGER: { /* A possibility exists that this is a whole-valued float where the * fractional part was left out due to being 0 (.0). It's not a big @@ -646,56 +511,57 @@ static QObject *parse_literal(JSONParserContext *ctxt) int64_t value; errno = 0; /* strtoll doesn't set errno on success */ - value = strtoll(token_get_value(token), NULL, 10); + value = strtoll(token->str, NULL, 10); if (errno != ERANGE) { - obj = QOBJECT(qint_from_int(value)); - break; + return QOBJECT(qint_from_int(value)); } /* fall through to JSON_FLOAT */ } case JSON_FLOAT: - /* FIXME dependent on locale */ - obj = QOBJECT(qfloat_from_double(strtod(token_get_value(token), NULL))); - break; + /* FIXME dependent on locale; a pervasive issue in QEMU */ + /* FIXME our lexer matches RFC 7159 in forbidding Inf or NaN, + * but those might be useful extensions beyond JSON */ + return QOBJECT(qfloat_from_double(strtod(token->str, NULL))); default: - goto out; + abort(); } - - return obj; - -out: - parser_context_restore(ctxt, saved_ctxt); - - return NULL; } static QObject *parse_value(JSONParserContext *ctxt, va_list *ap) { - QObject *obj; + JSONToken *token; - obj = parse_object(ctxt, ap); - if (obj == NULL) { - obj = parse_array(ctxt, ap); - } - if (obj == NULL) { - obj = parse_escape(ctxt, ap); - } - if (obj == NULL) { - obj = parse_keyword(ctxt); - } - if (obj == NULL) { - obj = parse_literal(ctxt); + token = parser_context_peek_token(ctxt); + if (token == NULL) { + parse_error(ctxt, NULL, "premature EOI"); + return NULL; } - return obj; + switch (token->type) { + case JSON_LCURLY: + return parse_object(ctxt, ap); + case JSON_LSQUARE: + return parse_array(ctxt, ap); + case JSON_ESCAPE: + return parse_escape(ctxt, ap); + case JSON_INTEGER: + case JSON_FLOAT: + case JSON_STRING: + return parse_literal(ctxt); + case JSON_KEYWORD: + return parse_keyword(ctxt); + default: + parse_error(ctxt, token, "expecting value"); + return NULL; + } } -QObject *json_parser_parse(QList *tokens, va_list *ap) +QObject *json_parser_parse(GQueue *tokens, va_list *ap) { return json_parser_parse_err(tokens, ap, NULL); } -QObject *json_parser_parse_err(QList *tokens, va_list *ap, Error **errp) +QObject *json_parser_parse_err(GQueue *tokens, va_list *ap, Error **errp) { JSONParserContext *ctxt = parser_context_new(tokens); QObject *result; |