lyfz_repos/经典版源码/common/cJson/cJSON_Utils.c

#include <ctype.h>
#include <string.h>
#include <stdlib.h>
#include <stdio.h>
#include "cJSON_Utils.h"

static char* cJSONUtils_strdup(const char* str)
{
	size_t len = 0;
	char *copy = NULL;

	len = strlen(str) + 1;
	if (!(copy = (char*)malloc(len)))
	{
		return NULL;
	}
	memcpy(copy, str, len);

	return copy;
}

static int cJSONUtils_strcasecmp(const char *s1, const char *s2)
{
	if (!s1)
	{
		return (s1 == s2) ? 0 : 1; /* both NULL? */
	}
	if (!s2)
	{
		return 1;
	}
	for(; tolower(*s1) == tolower(*s2); ++s1, ++s2)
	{
		if(*s1 == 0)
		{
			return 0;
		}
	}

	return tolower(*(const unsigned char *)s1) - tolower(*(const unsigned char *)s2);
}

/* JSON Pointer implementation: */
static int cJSONUtils_Pstrcasecmp(const char *a, const char *e)
{
	if (!a || !e)
	{
		return (a == e) ? 0 : 1; /* both NULL? */
	}
	for (; *a && *e && (*e != '/'); a++, e++) /* compare until next '/' */
	{
		if (*e == '~')
		{
			/* check for escaped '~' (~0) and '/' (~1) */
			if (!((e[1] == '0') && (*a == '~')) && !((e[1] == '1') && (*a == '/')))
			{
				/* invalid escape sequence or wrong character in *a */
				return 1;
			}
			else
			{
				e++;
			}
		}
		else if (tolower(*a) != tolower(*e))
		{
			return 1;
		}
	}
	if (((*e != 0) && (*e != '/')) != (*a != 0))
	{
		/* one string has ended, the other not */
		return 1;
	}

	return 0;
}

static int cJSONUtils_PointerEncodedstrlen(const char *s)
{
	int l = 0;
	for (; *s; s++, l++)
	{
		if ((*s == '~') || (*s == '/'))
		{
			l++;
		}
	}

	return l;
}

static void cJSONUtils_PointerEncodedstrcpy(char *d, const char *s)
{
	for (; *s; s++)
	{
		if (*s == '/')
		{
			*d++ = '~';
			*d++ = '1';
		}
		else if (*s == '~')
		{
			*d++ = '~';
			*d++ = '0';
		}
		else
		{
			*d++ = *s;
		}
	}

	*d = '\0';
}

char *cJSONUtils_FindPointerFromObjectTo(cJSON *object, cJSON *target)
{
	int type = object->type;
	int c = 0;
	cJSON *obj = 0;

	if (object == target)
	{
		/* found */
		return cJSONUtils_strdup("");
	}

	/* recursively search all children of the object */
	for (obj = object->child; obj; obj = obj->next, c++)
	{
		char *found = cJSONUtils_FindPointerFromObjectTo(obj, target);
		if (found)
		{
			if ((type & 0xFF) == cJSON_Array)
			{
				/* reserve enough memory for a 64 bit integer + '/' and '\0' */
				char *ret = (char*)malloc(strlen(found) + 23);
				sprintf(ret, "/%d%s", c, found); /* /<array_index><path> */
				free(found);

				return ret;
			}
			else if ((type & 0xFF) == cJSON_Object)
			{
				char *ret = (char*)malloc(strlen(found) + cJSONUtils_PointerEncodedstrlen(obj->string) + 2);
				*ret = '/';
				cJSONUtils_PointerEncodedstrcpy(ret + 1, obj->string);
				strcat(ret, found);
				free(found);

				return ret;
			}

			/* reached leaf of the tree, found nothing */
			free(found);
			return NULL;
		}
	}

	/* not found */
	return NULL;
}

cJSON *cJSONUtils_GetPointer(cJSON *object, const char *pointer)
{
	/* follow path of the pointer */
	while ((*pointer++ == '/') && object)
	{
		if ((object->type & 0xFF) == cJSON_Array)
		{
			int which = 0;
			/* parse array index */
			while ((*pointer >= '0') && (*pointer <= '9'))
			{
				which = (10 * which) + (*pointer++ - '0');
			}
			if (*pointer && (*pointer != '/'))
			{
				/* not end of string or new path token */
				return NULL;
			}
			object = cJSON_GetArrayItem(object, which);
		}
		else if ((object->type & 0xFF) == cJSON_Object)
		{
			object = object->child;
			/* GetObjectItem. */
			while (object && cJSONUtils_Pstrcasecmp(object->string, pointer))
			{
				object = object->next;
			}
			/* skip to the next path token or end of string */
			while (*pointer && (*pointer != '/'))
			{
				pointer++;
			}
		}
		else
		{
			return NULL;
		}
	}

	return object;
}

/* JSON Patch implementation. */
static void cJSONUtils_InplaceDecodePointerString(char *string)
{
	char *s2 = string;
	for (; *string; s2++, string++)
	{
		*s2 = (*string != '~')
			? (*string)
			: ((*(++string) == '0')
			? '~'
			: '/');
	}

	*s2 = '\0';
}

static cJSON *cJSONUtils_PatchDetach(cJSON *object, const char *path)
{
	char *parentptr = NULL;
	char *childptr = NULL;
	cJSON *parent = NULL;
	cJSON *ret = NULL;

	/* copy path and split it in parent and child */
	parentptr = cJSONUtils_strdup(path);
	childptr = strrchr(parentptr, '/'); /* last '/' */
	if (childptr)
	{
		/* split strings */
		*childptr++ = '\0';
	}
	parent = cJSONUtils_GetPointer(object, parentptr);
	cJSONUtils_InplaceDecodePointerString(childptr);

	if (!parent)
	{
		/* Couldn't find object to remove child from. */
		ret = NULL;
	}
	else if ((parent->type & 0xFF) == cJSON_Array)
	{
		ret = cJSON_DetachItemFromArray(parent, atoi(childptr));
	}
	else if ((parent->type & 0xFF) == cJSON_Object)
	{
		ret = cJSON_DetachItemFromObject(parent, childptr);
	}
	free(parentptr);

	/* return the detachted item */
	return ret;
}

static int cJSONUtils_Compare(cJSON *a, cJSON *b)
{
	if ((a->type & 0xFF) != (b->type & 0xFF))
	{
		/* mismatched type. */
		return -1;
	}
	switch (a->type & 0xFF)
	{
	case cJSON_Number:
		/* numeric mismatch. */
		return ((a->valueint != b->valueint) || (a->valuedouble != b->valuedouble)) ? -2 : 0;
	case cJSON_String:
		/* string mismatch. */
		return (strcmp(a->valuestring, b->valuestring) != 0) ? -3 : 0;
	case cJSON_Array:
		for (a = a->child, b = b->child; a && b; a = a->next, b = b->next)
		{
			int err = cJSONUtils_Compare(a, b);
			if (err)
			{
				return err;
			}
		}
		/* array size mismatch? (one of both children is not NULL) */
		return (a || b) ? -4 : 0;
	case cJSON_Object:
		cJSONUtils_SortObject(a);
		cJSONUtils_SortObject(b);
		a = a->child;
		b = b->child;
		while (a && b)
		{
			int err = 0;
			/* compare object keys */
			if (cJSONUtils_strcasecmp(a->string, b->string))
			{
				/* missing member */
				return -6;
			}
			err = cJSONUtils_Compare(a, b);
			if (err)
			{
				return err;
			}
			a = a->next;
			b = b->next;
		}
		/* object length mismatch (one of both children is not null) */
		return (a || b) ? -5 : 0;

	default:
		break;
	}
	/* null, true or false */
	return 0;
}

static int cJSONUtils_ApplyPatch(cJSON *object, cJSON *patch)
{
	cJSON *op = NULL;
	cJSON *path = NULL;
	cJSON *value = NULL;
	cJSON *parent = NULL;
	int opcode = 0;
	char *parentptr = NULL;
	char *childptr = NULL;

	op = cJSON_GetObjectItem(patch, "op");
	path = cJSON_GetObjectItem(patch, "path");
	if (!op || !path)
	{
		/* malformed patch. */
		return 2;
	}

	/* decode operation */
	if (!strcmp(op->valuestring, "add"))
	{
		opcode = 0;
	}
	else if (!strcmp(op->valuestring, "remove"))
	{
		opcode = 1;
	}
	else if (!strcmp(op->valuestring, "replace"))
	{
		opcode = 2;
	}
	else if (!strcmp(op->valuestring, "move"))
	{
		opcode = 3;
	}
	else if (!strcmp(op->valuestring, "copy"))
	{
		opcode = 4;
	}
	else if (!strcmp(op->valuestring, "test"))
	{
		/* compare value: {...} with the given path */
		return cJSONUtils_Compare(cJSONUtils_GetPointer(object, path->valuestring), cJSON_GetObjectItem(patch, "value"));
	}
	else
	{
		/* unknown opcode. */
		return 3;
	}

	/* Remove/Replace */
	if ((opcode == 1) || (opcode == 2))
	{
		/* Get rid of old. */
		cJSON_Delete(cJSONUtils_PatchDetach(object, path->valuestring));
		if (opcode == 1)
		{
			/* For Remove, this is job done. */
			return 0;
		}
	}

	/* Copy/Move uses "from". */
	if ((opcode == 3) || (opcode == 4))
	{
		cJSON *from = cJSON_GetObjectItem(patch, "from");
		if (!from)
		{
			/* missing "from" for copy/move. */
			return 4;
		}

		if (opcode == 3)
		{
			/* move */
			value = cJSONUtils_PatchDetach(object, from->valuestring);
		}
		if (opcode == 4)
		{
			/* copy */
			value = cJSONUtils_GetPointer(object, from->valuestring);
		}
		if (!value)
		{
			/* missing "from" for copy/move. */
			return 5;
		}
		if (opcode == 4)
		{
			value = cJSON_Duplicate(value, 1);
		}
		if (!value)
		{
			/* out of memory for copy/move. */
			return 6;
		}
	}
	else /* Add/Replace uses "value". */
	{
		value = cJSON_GetObjectItem(patch, "value");
		if (!value)
		{
			/* missing "value" for add/replace. */
			return 7;
		}
		value = cJSON_Duplicate(value, 1);
		if (!value)
		{
			/* out of memory for add/replace. */
			return 8;
		}
	}

	/* Now, just add "value" to "path". */

	/* split pointer in parent and child */
	parentptr = cJSONUtils_strdup(path->valuestring);
	childptr = strrchr(parentptr, '/');
	if (childptr)
	{
		*childptr++ = '\0';
	}
	parent = cJSONUtils_GetPointer(object, parentptr);
	cJSONUtils_InplaceDecodePointerString(childptr);

	/* add, remove, replace, move, copy, test. */
	if (!parent)
	{
		/* Couldn't find object to add to. */
		free(parentptr);
		cJSON_Delete(value);
		return 9;
	}
	else if ((parent->type & 0xFF) == cJSON_Array)
	{
		if (!strcmp(childptr, "-"))
		{
			cJSON_AddItemToArray(parent, value);
		}
		else
		{
			cJSON_InsertItemInArray(parent, atoi(childptr), value);
		}
	}
	else if ((parent->type & 0xFF) == cJSON_Object)
	{
		cJSON_DeleteItemFromObject(parent, childptr);
		cJSON_AddItemToObject(parent, childptr, value);
	}
	else
	{
		cJSON_Delete(value);
	}
	free(parentptr);

	return 0;
}

int cJSONUtils_ApplyPatches(cJSON *object, cJSON *patches)
{
	int err = 0;
	if ((patches->type & 0xFF) != cJSON_Array)
	{
		/* malformed patches. */
		return 1;
	}
	if (patches)
	{
		patches = patches->child;
	}
	while (patches)
	{
		if ((err = cJSONUtils_ApplyPatch(object, patches)))
		{
			return err;
		}
		patches = patches->next;
	}

	return 0;
}

static void cJSONUtils_GeneratePatch(cJSON *patches, const char *op, const char *path, const char *suffix, cJSON *val)
{
	cJSON *patch = cJSON_CreateObject();
	cJSON_AddItemToObject(patch, "op", cJSON_CreateString(op));
	if (suffix)
	{
		char *newpath = (char*)malloc(strlen(path) + cJSONUtils_PointerEncodedstrlen(suffix) + 2);
		cJSONUtils_PointerEncodedstrcpy(newpath + sprintf(newpath, "%s/", path), suffix);
		cJSON_AddItemToObject(patch, "path", cJSON_CreateString(newpath));
		free(newpath);
	}
	else
	{
		cJSON_AddItemToObject(patch, "path", cJSON_CreateString(path));
	}
	if (val)
	{
		cJSON_AddItemToObject(patch, "value", cJSON_Duplicate(val, 1));
	}
	cJSON_AddItemToArray(patches, patch);
}

void cJSONUtils_AddPatchToArray(cJSON *array, const char *op, const char *path, cJSON *val)
{
	cJSONUtils_GeneratePatch(array, op, path, 0, val);
}

static void cJSONUtils_CompareToPatch(cJSON *patches, const char *path, cJSON *from, cJSON *to)
{
	if ((from->type & 0xFF) != (to->type & 0xFF))
	{
		cJSONUtils_GeneratePatch(patches, "replace", path, 0, to);
		return;
	}

	switch ((from->type & 0xFF))
	{
	case cJSON_Number:
		if ((from->valueint != to->valueint) || (from->valuedouble != to->valuedouble))
		{
			cJSONUtils_GeneratePatch(patches, "replace", path, 0, to);
		}
		return;

	case cJSON_String:
		if (strcmp(from->valuestring, to->valuestring) != 0)
		{
			cJSONUtils_GeneratePatch(patches, "replace", path, 0, to);
		}
		return;

	case cJSON_Array:
		{
			int c = 0;
			char *newpath = (char*)malloc(strlen(path) + 23); /* Allow space for 64bit int. */
			/* generate patches for all array elements that exist in "from" and "to" */
			for (c = 0, from = from->child, to = to->child; from && to; from = from->next, to = to->next, c++)
			{
				sprintf(newpath, "%s/%d", path, c); /* path of the current array element */
				cJSONUtils_CompareToPatch(patches, newpath, from, to);
			}
			/* remove leftover elements from 'from' that are not in 'to' */
			for (; from; from = from->next, c++)
			{
				sprintf(newpath, "%d", c);
				cJSONUtils_GeneratePatch(patches, "remove", path, newpath, 0);
			}
			/* add new elements in 'to' that were not in 'from' */
			for (; to; to = to->next, c++)
			{
				cJSONUtils_GeneratePatch(patches, "add", path, "-", to);
			}
			free(newpath);
			return;
		}

	case cJSON_Object:
		{
			cJSON *a = NULL;
			cJSON *b = NULL;
			cJSONUtils_SortObject(from);
			cJSONUtils_SortObject(to);

			a = from->child;
			b = to->child;
			/* for all object values in the object with more of them */
			while (a || b)
			{
				int diff = (!a) ? 1 : ((!b) ? -1 : cJSONUtils_strcasecmp(a->string, b->string));
				if (!diff)
				{
					/* both object keys are the same */
					char *newpath = (char*)malloc(strlen(path) + cJSONUtils_PointerEncodedstrlen(a->string) + 2);
					cJSONUtils_PointerEncodedstrcpy(newpath + sprintf(newpath, "%s/", path), a->string);
					/* create a patch for the element */
					cJSONUtils_CompareToPatch(patches, newpath, a, b);
					free(newpath);
					a = a->next;
					b = b->next;
				}
				else if (diff < 0)
				{
					/* object element doesn't exist in 'to' --> remove it */
					cJSONUtils_GeneratePatch(patches, "remove", path, a->string, 0);
					a = a->next;
				}
				else
				{
					/* object element doesn't exist in 'from' --> add it */
					cJSONUtils_GeneratePatch(patches, "add", path, b->string, b);
					b = b->next;
				}
			}
			return;
		}

	default:
		break;
	}
}

cJSON* cJSONUtils_GeneratePatches(cJSON *from, cJSON *to)
{
	cJSON *patches = cJSON_CreateArray();
	cJSONUtils_CompareToPatch(patches, "", from, to);

	return patches;
}

/* sort lists using mergesort */
static cJSON *cJSONUtils_SortList(cJSON *list)
{
	cJSON *first = list;
	cJSON *second = list;
	cJSON *ptr = list;

	if (!list || !list->next)
	{
		/* One entry is sorted already. */
		return list;
	}

	while (ptr && ptr->next && (cJSONUtils_strcasecmp(ptr->string, ptr->next->string) < 0))
	{
		/* Test for list sorted. */
		ptr = ptr->next;
	}
	if (!ptr || !ptr->next)
	{
		/* Leave sorted lists unmodified. */
		return list;
	}

	/* reset ptr to the beginning */
	ptr = list;
	while (ptr)
	{
		/* Walk two pointers to find the middle. */
		second = second->next;
		ptr = ptr->next;
		/* advances ptr two steps at a time */
		if (ptr)
		{
			ptr = ptr->next;
		}
	}
	if (second && second->prev)
	{
		/* Split the lists */
		second->prev->next = NULL;
	}

	/* Recursively sort the sub-lists. */
	first = cJSONUtils_SortList(first);
	second = cJSONUtils_SortList(second);
	list = ptr = NULL;

	while (first && second) /* Merge the sub-lists */
	{
		if (cJSONUtils_strcasecmp(first->string, second->string) < 0)
		{
			if (!list)
			{
				/* start merged list with the first element of the first list */
				list = ptr = first;
			}
			else
			{
				/* add first element of first list to merged list */
				ptr->next = first;
				first->prev = ptr;
				ptr = first;
			}
			first = first->next;
		}
		else
		{
			if (!list)
			{
				/* start merged list with the first element of the second list */
				list = ptr = second;
			}
			else
			{
				/* add first element of second list to merged list */
				ptr->next = second;
				second->prev = ptr;
				ptr = second;
			}
			second = second->next;
		}
	}
	if (first)
	{
		/* Append rest of first list. */
		if (!list)
		{
			return first;
		}
		ptr->next = first;
		first->prev = ptr;
	}
	if (second)
	{
		/* Append rest of second list */
		if (!list)
		{
			return second;
		}
		ptr->next = second;
		second->prev = ptr;
	}

	return list;
}

void cJSONUtils_SortObject(cJSON *object)
{
	object->child = cJSONUtils_SortList(object->child);
}

cJSON* cJSONUtils_MergePatch(cJSON *target, cJSON *patch)
{
	if (!patch || ((patch->type & 0xFF) != cJSON_Object))
	{
		/* scalar value, array or NULL, just duplicate */
		cJSON_Delete(target);
		return cJSON_Duplicate(patch, 1);
	}

	if (!target || ((target->type & 0xFF) != cJSON_Object))
	{
		cJSON_Delete(target);
		target = cJSON_CreateObject();
	}

	patch = patch->child;
	while (patch)
	{
		if ((patch->type & 0xFF) == cJSON_NULL)
		{
			/* NULL is the indicator to remove a value, see RFC7396 */
			cJSON_DeleteItemFromObject(target, patch->string);
		}
		else
		{
			cJSON *replaceme = cJSON_DetachItemFromObject(target, patch->string);
			cJSON_AddItemToObject(target, patch->string, cJSONUtils_MergePatch(replaceme, patch));
		}
		patch = patch->next;
	}
	return target;
}

cJSON *cJSONUtils_GenerateMergePatch(cJSON *from, cJSON *to)
{
	cJSON *patch = NULL;
	if (!to)
	{
		/* patch to delete everything */
		return cJSON_CreateNull();
	}
	if (((to->type & 0xFF) != cJSON_Object) || !from || ((from->type & 0xFF) != cJSON_Object))
	{
		return cJSON_Duplicate(to, 1);
	}

	cJSONUtils_SortObject(from);
	cJSONUtils_SortObject(to);

	from = from->child;
	to = to->child;
	patch = cJSON_CreateObject();
	while (from || to)
	{
		int compare = from ? (to ? strcmp(from->string, to->string) : -1) : 1;
		if (compare < 0)
		{
			/* from has a value that to doesn't have -> remove */
			cJSON_AddItemToObject(patch, from->string, cJSON_CreateNull());
			from = from->next;
		}
		else if (compare > 0)
		{
			/* to has a value that from doesn't have -> add to patch */
			cJSON_AddItemToObject(patch, to->string, cJSON_Duplicate(to, 1));
			to = to->next;
		}
		else
		{
			/* object key exists in both objects */
			if (cJSONUtils_Compare(from, to))
			{
				/* not identical --> generate a patch */
				cJSON_AddItemToObject(patch, to->string, cJSONUtils_GenerateMergePatch(from, to));
			}
			/* next key in the object */
			from = from->next;
			to = to->next;
		}
	}
	if (!patch->child)
	{
		cJSON_Delete(patch);
		return NULL;
	}

	return patch;
}