On Wed, 2011-09-21 at 13:59 +0100, Anthony PERARD wrote:
> We use the yajl parser, but we need to make a tree from the parse result
> to use it outside the parser.
>
> So this patch include json_object struct that is used to hold the JSON
> data.
>
> Signed-off-by: Anthony PERARD <anthony.perard@xxxxxxxxxx>
I didn't review this again but I recall being happy with it last time
round so:
Acked-by: Ian Campbell <ian.campbell@xxxxxxxxxx>
> ---
> README | 1 +
> tools/libxl/Makefile | 5 +-
> tools/libxl/libxl_internal.h | 100 ++++++++
> tools/libxl/libxl_json.c | 560
> ++++++++++++++++++++++++++++++++++++++++++
> 4 files changed, 665 insertions(+), 1 deletions(-)
> create mode 100644 tools/libxl/libxl_json.c
>
> diff --git a/README b/README
> index ff154b2..c9bf699 100644
> --- a/README
> +++ b/README
> @@ -47,6 +47,7 @@ provided by your OS distributor:
> * Development install of openssl (e.g., openssl-dev)
> * Development install of x11 (e.g. xorg-x11-dev)
> * Development install of uuid (e.g. uuid-dev)
> + * Development install of yajl (e.g. libyajl-dev)
> * bridge-utils package (/sbin/brctl)
> * iproute package (/sbin/ip)
> * hotplug or udev
> diff --git a/tools/libxl/Makefile b/tools/libxl/Makefile
> index 1f6b418..e50874e 100644
> --- a/tools/libxl/Makefile
> +++ b/tools/libxl/Makefile
> @@ -32,9 +32,12 @@ endif
> LIBXL_OBJS-$(CONFIG_X86) += libxl_cpuid.o
> LIBXL_OBJS-$(CONFIG_IA64) += libxl_nocpuid.o
>
> +LIBXL_LIBS += -lyajl
> +
> LIBXL_OBJS = flexarray.o libxl.o libxl_create.o libxl_dm.o libxl_pci.o \
> libxl_dom.o libxl_exec.o libxl_xshelp.o
> libxl_device.o \
> - libxl_internal.o libxl_utils.o libxl_uuid.o
> $(LIBXL_OBJS-y)
> + libxl_internal.o libxl_utils.o libxl_uuid.o
> libxl_json.o \
> + $(LIBXL_OBJS-y)
> LIBXL_OBJS += _libxl_types.o libxl_flask.o _libxl_types_internal.o
>
> $(LIBXL_OBJS): CFLAGS += $(CFLAGS_libxenctrl) $(CFLAGS_libxenguest)
> $(CFLAGS_libxenstore) $(CFLAGS_libblktapctl)
> diff --git a/tools/libxl/libxl_internal.h b/tools/libxl/libxl_internal.h
> index d873243..f495e86 100644
> --- a/tools/libxl/libxl_internal.h
> +++ b/tools/libxl/libxl_internal.h
> @@ -387,4 +387,104 @@ _hidden int libxl__e820_alloc(libxl_ctx *ctx, uint32_t
> domid, libxl_domain_confi
> #define STRINGIFY(x) #x
> #define TOSTRING(x) STRINGIFY(x)
>
> +/* from libxl_json */
> +#include <yajl/yajl_gen.h>
> +
> +_hidden yajl_gen_status libxl__yajl_gen_asciiz(yajl_gen hand, const char
> *str);
> +
> +typedef enum {
> + JSON_ERROR,
> + JSON_NULL,
> + JSON_TRUE,
> + JSON_FALSE,
> + JSON_INTEGER,
> + JSON_DOUBLE,
> + JSON_STRING,
> + JSON_MAP,
> + JSON_ARRAY,
> + JSON_ANY
> +} libxl__json_node_type;
> +
> +typedef struct libxl__json_object {
> + libxl__json_node_type type;
> + union {
> + long i;
> + double d;
> + char *string;
> + /* List of libxl__json_object */
> + flexarray_t *array;
> + /* List of libxl__json_map_node */
> + flexarray_t *map;
> + } u;
> + struct libxl__json_object *parent;
> +} libxl__json_object;
> +
> +typedef struct {
> + char *map_key;
> + libxl__json_object *obj;
> +} libxl__json_map_node;
> +
> +typedef struct libxl__yajl_ctx libxl__yajl_ctx;
> +
> +static inline bool libxl__json_object_is_string(const libxl__json_object *o)
> +{
> + return o != NULL && o->type == JSON_STRING;
> +}
> +static inline bool libxl__json_object_is_integer(const libxl__json_object *o)
> +{
> + return o != NULL && o->type == JSON_INTEGER;
> +}
> +static inline bool libxl__json_object_is_map(const libxl__json_object *o)
> +{
> + return o != NULL && o->type == JSON_MAP;
> +}
> +static inline bool libxl__json_object_is_array(const libxl__json_object *o)
> +{
> + return o != NULL && o->type == JSON_ARRAY;
> +}
> +
> +static inline
> +const char *libxl__json_object_get_string(const libxl__json_object *o)
> +{
> + if (libxl__json_object_is_string(o))
> + return o->u.string;
> + else
> + return NULL;
> +}
> +static inline
> +flexarray_t *libxl__json_object_get_map(const libxl__json_object *o)
> +{
> + if (libxl__json_object_is_map(o))
> + return o->u.map;
> + else
> + return NULL;
> +}
> +static inline
> +flexarray_t *libxl__json_object_get_array(const libxl__json_object *o)
> +{
> + if (libxl__json_object_is_array(o))
> + return o->u.array;
> + else
> + return NULL;
> +}
> +static inline long libxl__json_object_get_integer(const libxl__json_object
> *o)
> +{
> + if (libxl__json_object_is_integer(o))
> + return o->u.i;
> + else
> + return -1;
> +}
> +
> +_hidden libxl__json_object *libxl__json_array_get(const libxl__json_object
> *o,
> + int i);
> +_hidden
> +libxl__json_map_node *libxl__json_map_node_get(const libxl__json_object *o,
> + int i);
> +_hidden const libxl__json_object *libxl__json_map_get(const char *key,
> + const libxl__json_object *o,
> + libxl__json_node_type
> expected_type);
> +_hidden void libxl__json_object_free(libxl__gc *gc, libxl__json_object *obj);
> +
> +_hidden libxl__json_object *libxl__json_parse(libxl__gc *gc, const char *s);
> +
> #endif
> diff --git a/tools/libxl/libxl_json.c b/tools/libxl/libxl_json.c
> new file mode 100644
> index 0000000..e771925
> --- /dev/null
> +++ b/tools/libxl/libxl_json.c
> @@ -0,0 +1,560 @@
> +/*
> + * Copyright (C) 2011 Citrix Ltd.
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU Lesser General Public License as published
> + * by the Free Software Foundation; version 2.1 only. with the special
> + * exception on linking described in file LICENSE.
> + *
> + * This program 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 Lesser General Public License for more details.
> + */
> +
> +#include <assert.h>
> +#include <string.h>
> +
> +#include <yajl/yajl_parse.h>
> +#include <yajl/yajl_gen.h>
> +
> +#include "libxl_internal.h"
> +
> +/* #define DEBUG_ANSWER */
> +
> +struct libxl__yajl_ctx {
> + libxl__gc *gc;
> + yajl_handle hand;
> + libxl__json_object *head;
> + libxl__json_object *current;
> +#ifdef DEBUG_ANSWER
> + yajl_gen g;
> +#endif
> +};
> +
> +#ifdef DEBUG_ANSWER
> +# define DEBUG_GEN_ALLOC(ctx) \
> + if ((ctx)->g == NULL) { \
> + yajl_gen_config conf = { 1, " " }; \
> + (ctx)->g = yajl_gen_alloc(&conf, NULL); \
> + }
> +# define DEBUG_GEN_FREE(ctx) \
> + if ((ctx)->g) yajl_gen_free((ctx)->g)
> +# define DEBUG_GEN(ctx, type) yajl_gen_##type(ctx->g)
> +# define DEBUG_GEN_VALUE(ctx, type, value) yajl_gen_##type(ctx->g, value)
> +# define DEBUG_GEN_STRING(ctx, str, n) yajl_gen_string(ctx->g, str, n)
> +# define DEBUG_GEN_REPORT(yajl_ctx) \
> + do { \
> + const unsigned char *buf = NULL; \
> + unsigned int len = 0; \
> + yajl_gen_get_buf((yajl_ctx)->g, &buf, &len); \
> + LIBXL__LOG(libxl__gc_owner((yajl_ctx)->gc), \
> + LIBXL__LOG_DEBUG, "response:\n%s", buf); \
> + yajl_gen_free((yajl_ctx)->g); \
> + (yajl_ctx)->g = NULL; \
> + } while (0)
> +#else
> +# define DEBUG_GEN_ALLOC(ctx) ((void)0)
> +# define DEBUG_GEN_FREE(ctx) ((void)0)
> +# define DEBUG_GEN(ctx, type) ((void)0)
> +# define DEBUG_GEN_VALUE(ctx, type, value) ((void)0)
> +# define DEBUG_GEN_STRING(ctx, value, lenght) ((void)0)
> +# define DEBUG_GEN_REPORT(ctx) ((void)0)
> +#endif
> +
> +/*
> + * YAJL Helper
> + */
> +
> +yajl_gen_status libxl__yajl_gen_asciiz(yajl_gen hand, const char *str)
> +{
> + return yajl_gen_string(hand, (const unsigned char *)str, strlen(str));
> +}
> +
> +
> +/*
> + * libxl__json_object helper functions
> + */
> +
> +static libxl__json_object *json_object_alloc(libxl__gc *gc,
> + libxl__json_node_type type)
> +{
> + libxl__json_object *obj;
> +
> + obj = calloc(1, sizeof (libxl__json_object));
> + if (obj == NULL) {
> + LIBXL__LOG_ERRNO(libxl__gc_owner(gc), LIBXL__LOG_ERROR,
> + "Failed to allocate a libxl__json_object");
> + return NULL;
> + }
> +
> + obj->type = type;
> +
> + if (type == JSON_MAP || type == JSON_ARRAY) {
> + flexarray_t *array = flexarray_make(1, 1);
> + if (array == NULL) {
> + LIBXL__LOG_ERRNO(libxl__gc_owner(gc), LIBXL__LOG_ERROR,
> + "Failed to allocate a flexarray");
> + free(obj);
> + return NULL;
> + }
> + if (type == JSON_MAP)
> + obj->u.map = array;
> + else
> + obj->u.array = array;
> + }
> +
> + return obj;
> +}
> +
> +static int json_object_append_to(libxl__gc *gc,
> + libxl__json_object *obj,
> + libxl__json_object *dst)
> +{
> + assert(dst != NULL);
> +
> + switch (dst->type) {
> + case JSON_MAP: {
> + libxl__json_map_node *last;
> +
> + if (dst->u.map->count == 0) {
> + LIBXL__LOG(libxl__gc_owner(gc), LIBXL__LOG_ERROR,
> + "Try to add a value to an empty map (with no key)");
> + return -1;
> + }
> + flexarray_get(dst->u.map, dst->u.map->count - 1, (void**)&last);
> + last->obj = obj;
> + break;
> + }
> + case JSON_ARRAY:
> + if (flexarray_append(dst->u.array, obj) == 2) {
> + LIBXL__LOG_ERRNO(libxl__gc_owner(gc), LIBXL__LOG_ERROR,
> + "Failed to grow a flexarray");
> + return -1;
> + }
> + break;
> + default:
> + LIBXL__LOG(libxl__gc_owner(gc), LIBXL__LOG_ERROR,
> + "Try append an object is not a map/array (%i)\n",
> + dst->type);
> + return -1;
> + }
> +
> + obj->parent = dst;
> + return 0;
> +}
> +
> +void libxl__json_object_free(libxl__gc *gc, libxl__json_object *obj)
> +{
> + int index = 0;
> +
> + if (obj == NULL)
> + return;
> + switch (obj->type) {
> + case JSON_STRING:
> + free(obj->u.string);
> + break;
> + case JSON_MAP: {
> + libxl__json_map_node *node = NULL;
> +
> + for (index = 0; index < obj->u.map->count; index++) {
> + if (flexarray_get(obj->u.map, index, (void**)&node) != 0)
> + break;
> + libxl__json_object_free(gc, node->obj);
> + free(node->map_key);
> + free(node);
> + node = NULL;
> + }
> + flexarray_free(obj->u.map);
> + break;
> + }
> + case JSON_ARRAY: {
> + libxl__json_object *node = NULL;
> + break;
> +
> + for (index = 0; index < obj->u.array->count; index++) {
> + if (flexarray_get(obj->u.array, index, (void**)&node) != 0)
> + break;
> + libxl__json_object_free(gc, node);
> + node = NULL;
> + }
> + flexarray_free(obj->u.array);
> + break;
> + }
> + default:
> + break;
> + }
> + free(obj);
> +}
> +
> +libxl__json_object *libxl__json_array_get(const libxl__json_object *o, int i)
> +{
> + flexarray_t *array = NULL;
> + libxl__json_object *obj = NULL;
> +
> + if ((array = libxl__json_object_get_array(o)) == NULL) {
> + return NULL;
> + }
> +
> + if (i >= array->count)
> + return NULL;
> +
> + if (flexarray_get(array, i, (void**)&obj) != 0)
> + return NULL;
> +
> + return obj;
> +}
> +
> +libxl__json_map_node *libxl__json_map_node_get(const libxl__json_object *o,
> + int i)
> +{
> + flexarray_t *array = NULL;
> + libxl__json_map_node *obj = NULL;
> +
> + if ((array = libxl__json_object_get_map(o)) == NULL) {
> + return NULL;
> + }
> +
> + if (i >= array->count)
> + return NULL;
> +
> + if (flexarray_get(array, i, (void**)&obj) != 0)
> + return NULL;
> +
> + return obj;
> +}
> +
> +const libxl__json_object *libxl__json_map_get(const char *key,
> + const libxl__json_object *o,
> + libxl__json_node_type
> expected_type)
> +{
> + flexarray_t *maps = NULL;
> + int index = 0;
> +
> + if (libxl__json_object_is_map(o)) {
> + libxl__json_map_node *node = NULL;
> +
> + maps = o->u.map;
> + for (index = 0; index < maps->count; index++) {
> + if (flexarray_get(maps, index, (void**)&node) != 0)
> + return NULL;
> + if (strcmp(key, node->map_key) == 0) {
> + if (expected_type == JSON_ANY
> + || (node->obj && node->obj->type == expected_type)) {
> + return node->obj;
> + } else {
> + return NULL;
> + }
> + }
> + }
> + }
> + return NULL;
> +}
> +
> +
> +/*
> + * JSON callbacks
> + */
> +
> +static int json_callback_null(void *opaque)
> +{
> + libxl__yajl_ctx *ctx = opaque;
> + libxl__json_object *obj;
> +
> + DEBUG_GEN(ctx, null);
> +
> + if ((obj = json_object_alloc(ctx->gc, JSON_NULL)) == NULL)
> + return 0;
> +
> + if (json_object_append_to(ctx->gc, obj, ctx->current) == -1) {
> + libxl__json_object_free(ctx->gc, obj);
> + return 0;
> + }
> +
> + return 1;
> +}
> +
> +static int json_callback_boolean(void *opaque, int boolean)
> +{
> + libxl__yajl_ctx *ctx = opaque;
> + libxl__json_object *obj;
> +
> + DEBUG_GEN_VALUE(ctx, bool, boolean);
> +
> + if ((obj = json_object_alloc(ctx->gc,
> + boolean ? JSON_TRUE : JSON_FALSE)) == NULL)
> + return 0;
> +
> + if (json_object_append_to(ctx->gc, obj, ctx->current) == -1) {
> + libxl__json_object_free(ctx->gc, obj);
> + return 0;
> + }
> +
> + return 1;
> +}
> +
> +static int json_callback_integer(void *opaque, long value)
> +{
> + libxl__yajl_ctx *ctx = opaque;
> + libxl__json_object *obj;
> +
> + DEBUG_GEN_VALUE(ctx, integer, value);
> +
> + if ((obj = json_object_alloc(ctx->gc, JSON_INTEGER)) == NULL)
> + return 0;
> + obj->u.i = value;
> +
> + if (json_object_append_to(ctx->gc, obj, ctx->current) == -1) {
> + libxl__json_object_free(ctx->gc, obj);
> + return 0;
> + }
> +
> + return 1;
> +}
> +
> +static int json_callback_double(void *opaque, double value)
> +{
> + libxl__yajl_ctx *ctx = opaque;
> + libxl__json_object *obj;
> +
> + DEBUG_GEN_VALUE(ctx, double, value);
> +
> + if ((obj = json_object_alloc(ctx->gc, JSON_DOUBLE)) == NULL)
> + return 0;
> + obj->u.d = value;
> +
> + if (json_object_append_to(ctx->gc, obj, ctx->current) == -1) {
> + libxl__json_object_free(ctx->gc, obj);
> + return 0;
> + }
> +
> + return 1;
> +}
> +
> +static int json_callback_string(void *opaque, const unsigned char *str,
> + unsigned int len)
> +{
> + libxl__yajl_ctx *ctx = opaque;
> + char *t = NULL;
> + libxl__json_object *obj = NULL;
> +
> + t = malloc(len + 1);
> + if (t == NULL) {
> + LIBXL__LOG_ERRNO(libxl__gc_owner(ctx->gc), LIBXL__LOG_ERROR,
> + "Failed to allocate");
> + return 0;
> + }
> +
> + DEBUG_GEN_STRING(ctx, str, len);
> +
> + strncpy(t, (const char *) str, len);
> + t[len] = 0;
> +
> + if ((obj = json_object_alloc(ctx->gc, JSON_STRING)) == NULL) {
> + free(t);
> + return 0;
> + }
> + obj->u.string = t;
> +
> + if (json_object_append_to(ctx->gc, obj, ctx->current) == -1) {
> + libxl__json_object_free(ctx->gc, obj);
> + return 0;
> + }
> +
> + return 1;
> +}
> +
> +static int json_callback_map_key(void *opaque, const unsigned char *str,
> + unsigned int len)
> +{
> + libxl__yajl_ctx *ctx = opaque;
> + char *t = NULL;
> + libxl__json_object *obj = ctx->current;
> +
> + t = malloc(len + 1);
> + if (t == NULL) {
> + LIBXL__LOG_ERRNO(libxl__gc_owner(ctx->gc), LIBXL__LOG_ERROR,
> + "Failed to allocate");
> + return 0;
> + }
> +
> + DEBUG_GEN_STRING(ctx, str, len);
> +
> + strncpy(t, (const char *) str, len);
> + t[len] = 0;
> +
> + if (libxl__json_object_is_map(obj)) {
> + libxl__json_map_node *node = malloc(sizeof (libxl__json_map_node));
> + if (node == NULL) {
> + LIBXL__LOG_ERRNO(libxl__gc_owner(ctx->gc), LIBXL__LOG_ERROR,
> + "Failed to allocate");
> + return 0;
> + }
> +
> + node->map_key = t;
> + node->obj = NULL;
> +
> + if (flexarray_append(obj->u.map, node) == 2) {
> + LIBXL__LOG_ERRNO(libxl__gc_owner(ctx->gc), LIBXL__LOG_ERROR,
> + "Failed to grow a flexarray");
> + return 0;
> + }
> + } else {
> + LIBXL__LOG(libxl__gc_owner(ctx->gc), LIBXL__LOG_ERROR,
> + "Current json object is not a map");
> + return 0;
> + }
> +
> + return 1;
> +}
> +
> +static int json_callback_start_map(void *opaque)
> +{
> + libxl__yajl_ctx *ctx = opaque;
> + libxl__json_object *obj = NULL;
> +
> + DEBUG_GEN(ctx, map_open);
> +
> + if ((obj = json_object_alloc(ctx->gc, JSON_MAP)) == NULL)
> + return 0;
> +
> + if (ctx->current) {
> + if (json_object_append_to(ctx->gc, obj, ctx->current) == -1) {
> + libxl__json_object_free(ctx->gc, obj);
> + return 0;
> + }
> + }
> +
> + ctx->current = obj;
> + if (ctx->head == NULL) {
> + ctx->head = obj;
> + }
> +
> + return 1;
> +}
> +
> +static int json_callback_end_map(void *opaque)
> +{
> + libxl__yajl_ctx *ctx = opaque;
> +
> + DEBUG_GEN(ctx, map_close);
> +
> + if (ctx->current) {
> + ctx->current = ctx->current->parent;
> + } else {
> + LIBXL__LOG(libxl__gc_owner(ctx->gc), LIBXL__LOG_ERROR,
> + "No current libxl__json_object, cannot use his parent.");
> + return 0;
> + }
> +
> + return 1;
> +}
> +
> +static int json_callback_start_array(void *opaque)
> +{
> + libxl__yajl_ctx *ctx = opaque;
> + libxl__json_object *obj = NULL;
> +
> + DEBUG_GEN(ctx, array_open);
> +
> + if ((obj = json_object_alloc(ctx->gc, JSON_ARRAY)) == NULL)
> + return 0;
> +
> + if (ctx->current) {
> + if (json_object_append_to(ctx->gc, obj, ctx->current) == -1) {
> + libxl__json_object_free(ctx->gc, obj);
> + return 0;
> + }
> + }
> +
> + ctx->current = obj;
> + if (ctx->head == NULL) {
> + ctx->head = obj;
> + }
> +
> + return 1;
> +}
> +
> +static int json_callback_end_array(void *opaque)
> +{
> + libxl__yajl_ctx *ctx = opaque;
> +
> + DEBUG_GEN(ctx, array_close);
> +
> + if (ctx->current) {
> + ctx->current = ctx->current->parent;
> + } else {
> + LIBXL__LOG(libxl__gc_owner(ctx->gc), LIBXL__LOG_ERROR,
> + "No current libxl__json_object, cannot use his parent.");
> + return 0;
> + }
> +
> + return 1;
> +}
> +
> +static yajl_callbacks callbacks = {
> + json_callback_null,
> + json_callback_boolean,
> + json_callback_integer,
> + json_callback_double,
> + NULL,
> + json_callback_string,
> + json_callback_start_map,
> + json_callback_map_key,
> + json_callback_end_map,
> + json_callback_start_array,
> + json_callback_end_array
> +};
> +
> +static void yajl_ctx_free(libxl__yajl_ctx *yajl_ctx)
> +{
> + if (yajl_ctx->hand) {
> + yajl_free(yajl_ctx->hand);
> + yajl_ctx->hand = NULL;
> + }
> + DEBUG_GEN_FREE(yajl_ctx);
> +}
> +
> +libxl__json_object *libxl__json_parse(libxl__gc *gc, const char *s)
> +{
> + yajl_status status;
> + libxl__yajl_ctx yajl_ctx;
> +
> + memset(&yajl_ctx, 0, sizeof (yajl_ctx));
> + yajl_ctx.gc = gc;
> +
> + DEBUG_GEN_ALLOC(&yajl_ctx);
> +
> + if (yajl_ctx.hand == NULL) {
> + yajl_parser_config cfg = {
> + .allowComments = 1,
> + .checkUTF8 = 1,
> + };
> + yajl_ctx.hand = yajl_alloc(&callbacks, &cfg, NULL, &yajl_ctx);
> + }
> + status = yajl_parse(yajl_ctx.hand, (const unsigned char *)s, strlen(s));
> + status = yajl_parse_complete(yajl_ctx.hand);
> +
> + if (status == yajl_status_ok) {
> + libxl__json_object *o = yajl_ctx.head;
> +
> + DEBUG_GEN_REPORT(&yajl_ctx);
> +
> + yajl_ctx.head = NULL;
> +
> + yajl_ctx_free(&yajl_ctx);
> + return o;
> + } else {
> + unsigned char *str = yajl_get_error(yajl_ctx.hand, 1,
> + (const unsigned char *)s,
> + strlen(s));
> +
> + LIBXL__LOG(libxl__gc_owner(gc), LIBXL__LOG_ERROR,
> + "yajl error: %s", str);
> + yajl_free_error(yajl_ctx.hand, str);
> +
> + libxl__json_object_free(gc, yajl_ctx.head);
> + yajl_ctx_free(&yajl_ctx);
> + return NULL;
> + }
> +}
> --
> Anthony PERARD
>
_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel
|
Home