在执行字符串操作某些错误 [英] Some error while performing string operations
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问题描述
下面是我的code：
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <json/json.h>
#include <curl/curl.h>
#include <sys/types.h>
#include <db.h>
#define DATABASE "access.db"
int db_json(char *val, char *key1);
void json_parse(char* str);
struct MemoryStruct {
char *memory;
size_t size;
};
char *begin = "<return>";
char *end = "</return>";
char *token;
char *json;
char *newstr = NULL;
char *str = NULL;
char *str1 = NULL;
char *str2 = NULL;
char *str3 = NULL;
char *finalstr = NULL;
char *str4 = NULL;
static size_t
WriteMemoryCallback(void *contents, size_t size, size_t nmemb, void *userp)
{
size_t realsize = size * nmemb;
struct MemoryStruct *mem = (struct MemoryStruct *)userp;
mem->memory = realloc(mem->memory, mem->size + realsize + 1);
if (mem->memory == NULL) {
/* out of memory! */
printf("not enough memory (realloc returned NULL)\n");
exit(EXIT_FAILURE);
}
memcpy(&(mem->memory[mem->size]), contents, realsize);
mem->size += realsize;
mem->memory[mem->size] = 0;
return realsize;
}
char *replace(const char *s, const char *old, const char *new)
{
char *ret;
int i, count = 0;
size_t newlen = strlen(new);
size_t oldlen = strlen(old);
for (i = 0; s[i] != '\0'; i++) {
if (strstr(&s[i], old) == &s[i]) {
count++;
i += oldlen - 1;
}
}
ret = malloc(i + count * (newlen - oldlen));
if (ret == NULL)
exit(EXIT_FAILURE);
i = 0;
while (*s) {
if (strstr(s, old) == s) {
strcpy(&ret[i], new);
i += newlen;
s += oldlen;
} else
ret[i++] = *s++;
}
ret[i] = '\0';
return ret;
}
void json_parse(char *str) {
json_object * jobj = json_tokener_parse(str);
enum json_type type;
json_object_object_foreach(jobj, key, val) {
type = json_object_get_type(val);
switch (type) {
case json_type_string: printf("type: json_type_string, ");
printf("value: %s\n", json_object_get_string(val));
printf("%s\n",key);
db_json(json_object_get_string(val), key);
break;
}
}
}
int db_json(char *val, char *key1) {
typedef struct {
char data1[500];
} pearson_record;
pearson_record s;
int i =0;
DB *dbp;
DBT key, data;
int ret, t_ret;
int recno;
if ((ret = db_create(&dbp, NULL, 0)) != 0) {
fprintf(stderr, "db_create: %s\n", db_strerror(ret));
exit (1);
}
// if ((ret = dbp->set_flags(dbp, DB_RECNUM)) != 0) {
// fprintf(stderr, "db_create: %s\n", db_strerror(ret));
// exit (1);
// }
if ((ret = dbp->open(dbp,
NULL, DATABASE, NULL, DB_BTREE, DB_CREATE, 0664)) != 0) {
dbp->err(dbp, ret, "%s", DATABASE);
goto err;
}
printf("data: %s\n",val);
strncpy(s.data1, val, strlen(val)+1);
//printf("chk %\n",jvalue);
recno = 10;
memset(&key, 0, sizeof(key));
memset(&data, 0, sizeof(data));
//memset(&s, 0, sizeof(struct pearson_record));
key.data = key1;
key.size = sizeof(key1);
data.data = &s;
data.size = sizeof(s);
if ((ret = dbp->put(dbp, NULL, &key,&data,0)) == 0)
printf("db: %s: key stored.\n", (char *)key.data);
else
{
dbp->err(dbp, ret, "DB->put");
goto err;
}
pearson_record *ppr;
if ((ret = dbp->get(dbp, NULL, &key, &data, 0)) == 0) {
ppr = (pearson_record *) data.data;
printf("db: %s: key retrieved: data was %s %d\n",
(char *)key.data, ppr->data1, data.size);
}
else {
dbp->err(dbp, ret, "DB->get");
goto err;
}
err: if ((t_ret = dbp->close(dbp, 0)) != 0 && ret == 0)
ret = t_ret;
exit(ret);
}
int main(void)
{
CURL *curl;
CURLcode res;
struct MemoryStruct chunk;
chunk.memory = malloc(1); /* will be grown as needed by the realloc above */
chunk.size = 0; /* no data at this point */
struct curl_slist *headerlist=NULL;
const char *temp = "<?xml version=\"1.0\" encoding=\"utf-8\"?> <S:Envelope xmlns:S=\"http://schemas.xmlsoap.org/soap/envelope/\"> <S:Header/> <S:Body> <ns2:getExtracurricular xmlns:ns2=\"http://desktop/\"> <deviceID>10:2E:AF:EB:6F:DB</deviceID> </ns2:getExtracurricular> </S:Body> </S:Envelope>";
curl = curl_easy_init();
if(curl) {
/* First set the URL that is about to receive our POST. This URL can
just as well be a https:// URL if that is what should receive the
data. */
curl_easy_setopt(curl, CURLOPT_URL, "http://eon.sdsu.edu:8080/SmartbadgePortal/PersonalInterestsService");
/* Now specify the POST data */
curl_easy_setopt(curl, CURLOPT_VERBOSE, 1L);
headerlist = curl_slist_append(headerlist, "Content-Type: text/xml");
curl_easy_setopt(curl, CURLOPT_POSTFIELDS, temp);
curl_easy_setopt(curl, CURLOPT_HTTPHEADER, headerlist);
/* send all data to this function */
curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, WriteMemoryCallback);
/* we pass our 'chunk' struct to the callback function */
curl_easy_setopt(curl, CURLOPT_WRITEDATA, (void *)&chunk);
/* Perform the request, res will get the return code */
res = curl_easy_perform(curl);
printf("%lu bytes retrieved\n", (long)chunk.size);
//printf("%s data received\n", chunk.memory);
token = strstr(chunk.memory, begin);
json = token + strlen(begin);
token = strstr(json, end);
*token = 0x00;
printf("%s\n",json);
newstr = replace(json, """, "\"");
printf("%s\n",newstr);
str = replace(newstr, "\"", "\\\"");
printf("%s\n",str);
str1 = replace(str, "\"[", "\"");
printf("%s\n",str1);
str2 = replace(str1, "]\\" , "\\");
printf("%s\n",str2);
str3 = replace(str2, "{" , "\"{");
printf("%s\n",str3);
finalstr = replace(str3, "}" , "}\"");
str4 = replace(finalstr, "))1" , "");
printf("%s\n", finalstr);
printf ("JSON string: %s\n", str4);
json_parse(str4);
if(chunk.memory)
free(chunk.memory);
/* always cleanup */
curl_easy_cleanup(curl);
}
return 0;
}
我收到分割错误，当我传递一个字符串到我的JSON的功能。我做了GDB以下是我的错误结果：
I am getting segmentation error when I am passing a string to my JSON function. I did gdb and below is my error result:
(gdb) print str
$1 = 0x28c90 "\"{\\\"1\\\":\\\"25,11,10,2,87,84,85,67\\\"}\"\251\002"
(gdb) print str4
$2 = 0x28c90 "\"{\\\"1\\\":\\\"25,11,10,2,87,84,85,67\\\"}\"\251\002"
(gdb) print finalstr
$3 = 0x28c60 "\"{\\\"1\\\":\\\"25,11,10,2,87,84,85,67\\\"}\"))1"
(gdb) print str3
$4 = 0x28c30 "\"{\\\"1\\\":\\\"25,11,10,2,87,84,85,67\\\"}))1"
(gdb) print str2
$5 = 0x28c08 "{\\\"1\\\":\\\"25,11,10,2,87,84,85,67\\\"}))1"
(gdb) print str1
$6 = 0x28be0 "{\\\"1\\\":\\\"25,11,10,2,87,84,85,67]\\\"}))"
(gdb) print str
$7 = 0x28c90 "\"{\\\"1\\\":\\\"25,11,10,2,87,84,85,67\\\"}\"\251\002"
(gdb) print newstr
$8 = 0x28a50 "{\"1\":\"[25,11,10,2,87,84,85,67]\"}"
所以我觉得有一个在我的方式替换功能工作的一些问题，因为它是添加额外字符来我的字符串\\ 251 \\ 002，在发送。
So I feel there is some problem in the way my replace function is working, because it is adding extra characters to my string "\251\002", while sending.
如果有人能帮助我一下吧，这将是巨大的。谢谢！
if anybody can help me with it, it would be great. Thanks!!!
推荐答案
RET =的malloc（I +数*（newlen - oldlen））; 是1短。结果
使用 = RET的malloc（I +数*（newlen - oldlen）+ 1）;
<一个href=\"http://stackoverflow.com/questions/25358392/c-string-replace-in-loop-c-beginner/25369468#25369468\">Ref
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