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| #include <stdio.h>
#include <string.h>
#include <pcre.h>
#include <stdbool.h>
#include <ctype.h>
#define MAX_PATTERN_LENGTH 1000
#define MAX_SUBJECT_LENGTH 1000
#define MAX_MATCHES 100
typedef struct {
int start;
int end;
} match_t;
int match_regex(const char* regex, const char* subject, match* matches, int max_matches) {
char pattern[MAX_PATTERN_LENGTH];
int options = 0;
const char* error;
int erroffset;
pcre* re;
int rc;
int ovector[MAX_MATCHES * 3];
int match_count = 0;
bool global = false;
// 解析正则表达式和选项
const char* pattern_start = strchr(regex, '/');
const char* pattern_end = strrchr(regex, '/');
if (pattern_start == NULL || pattern_end == NULL || pattern_start == pattern_end) {
printf("Invalid regex format. Use /pattern/options\n");
return -1;
}
// 提取模式
int pattern_length = pattern_end - pattern_start - 1;
strncpy(pattern, pattern_start + 1, pattern_length);
pattern[pattern_length] = '\0';
// 解析选项
const char* options_start = pattern_end + 1;
while (*options_start) {
switch (tolower(*options_start)) {
case 'i': options |= PCRE_CASELESS; break;
case 'm': options |= PCRE_MULTILINE; break;
case 's': options |= PCRE_DOTALL; break;
case 'x': options |= PCRE_EXTENDED; break;
case 'g': global = true; break;
default:
printf("Unknown option: %c\n", *options_start);
return -1;
}
options_start++;
}
// 编译正则表达式
re = pcre_compile(pattern, options, &error, &erroffset, NULL);
if (re == NULL) {
printf("PCRE compilation failed at offset %d: %s\n", erroffset, error);
return -1;
}
// 执行匹配
int subject_length = strlen(subject);
int offset = 0;
do {
rc = pcre_exec(re, NULL, subject, subject_length, offset, 0, ovector, MAX_MATCHES * 3);
if (rc < 0) {
if (rc != PCRE_ERROR_NOMATCH) {
printf("Matching error %d\n", rc);
}
break;
}
for (int i = 0; i < rc && match_count < max_matches; i++) {
matches[match_count].start = ovector[i*2];
matches[match_count].end = ovector[i*2+1];
match_count++;
}
offset = ovector[1];
} while (global && offset < subject_length && match_count < max_matches);
// 释放编译后的正则表达式
pcre_free(re);
return match_count;
}
void print_matches(const char* subject, match_t* matches, int match_count) {
for (int i = 0; i < match_count; i++) {
printf("match %d: %.*s\n", i + 1, matches[i].end - matches[i].start, subject + matches[i].start);
}
}
int main() {
char regex[MAX_PATTERN_LENGTH];
char subject[MAX_SUBJECT_LENGTH];
match_t matches[MAX_MATCHES];
int match_count;
printf("Enter regex (in /pattern/options format): ");
fgets(regex, sizeof(regex), stdin);
regex[strcspn(regex, "\n")] = 0; // 移除换行符
printf("Enter subject string: ");
fgets(subject, sizeof(subject), stdin);
subject[strcspn(subject, "\n")] = 0; // 移除换行符
match_count = match_regex(regex, subject, matches, MAX_MATCHES);
if (match_count >= 0) {
printf("Found %d matches:\n", match_count);
print_matches(subject, matches, match_count);
}
return 0;
}
|
