From ab43b394ac2044fb6d3f7d3d0cde552e9fc5ecbe Mon Sep 17 00:00:00 2001
From: yangwentong <425822674@qq.com>
Date: Fri, 28 Oct 2022 01:09:02 +0800
Subject: [PATCH] =?UTF-8?q?re2.cc=E4=B8=AD=E7=9A=84Rewrite=E4=BD=BF?=
 =?UTF-8?q?=E7=94=A8Rust=E5=AE=9E=E7=8E=B0?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 re2/re2.cc                | 50 +++++++-----------------
 regex-capi/include/rure.h |  6 +++
 regex-capi/src/rure.rs    | 81 +++++++++++++++++++++++++++++++++++++++
 3 files changed, 100 insertions(+), 37 deletions(-)

diff --git a/re2/re2.cc b/re2/re2.cc
index 524d47c..e36c494 100644
--- a/re2/re2.cc
+++ b/re2/re2.cc
@@ -734,44 +734,20 @@ namespace re2
                     const StringPiece *vec,
                     int veclen) const
   {
-    for (const char *s = rewrite.data(), *end = s + rewrite.size();
-         s < end; s++)
-    {
-      if (*s != '\\')
-      {
-        out->push_back(*s);
-        continue;
-      }
-      s++;
-      int c = (s < end) ? *s : -1;
-      if (isdigit(c))
-      {
-        int n = (c - '0');
-        if (n >= veclen)
-        {
-          if (options_.log_errors())
-          {
-            LOG(ERROR) << "invalid substitution \\" << n
-                       << " from " << veclen << " groups";
-          }
-          return false;
-        }
-        StringPiece snip = vec[n];
-        if (!snip.empty())
-          out->append(snip.data(), snip.size());
-      }
-      else if (c == '\\')
-      {
-        out->push_back('\\');
-      }
-      else
-      {
-        if (options_.log_errors())
-          LOG(ERROR) << "invalid rewrite pattern: " << rewrite.data();
-        return false;
-      }
+    size_t len = rewrite.length();
+    const char *rewrites[veclen];
+    size_t rewrites_lengths[veclen];
+    for(int i = 0; i < veclen; i++) {
+      rewrites[i] = vec[i].data();
+      rewrites_lengths[i] = vec[i].size();
     }
-    return true;
+    const char *result = rure_rewrite((const uint8_t *)rewrite.data(), len, (const uint8_t **)rewrites, 
+                                    rewrites_lengths, (size_t)veclen);
+    if(result != NULL) {
+      out->assign(result);
+      return true;
+    }
+    return false;
   }
 
   /***** Parsers for various types *****/
diff --git a/regex-capi/include/rure.h b/regex-capi/include/rure.h
index 32443b5..31d719a 100644
--- a/regex-capi/include/rure.h
+++ b/regex-capi/include/rure.h
@@ -618,6 +618,12 @@ bool rure_check_rewrite_string(const char *rewrite, int max_token);
 */
 const char *rure_rewrite_str_convert(const uint8_t *rewrite, size_t len);
 
+/*
+ * Similar to Rewrite function in RE2.
+*/
+const char *rure_rewrite(const uint8_t *rewrite, size_t len, const uint8_t **vecs,
+                const size_t *vecs_lengths, size_t vecs_count);
+
 #ifdef __cplusplus
 }
 #endif
\ No newline at end of file
diff --git a/regex-capi/src/rure.rs b/regex-capi/src/rure.rs
index a101770..eb17613 100644
--- a/regex-capi/src/rure.rs
+++ b/regex-capi/src/rure.rs
@@ -833,4 +833,85 @@ ffi_fn! {
         };
         rure_str.into_raw() as *const c_char
     }
+}
+
+ffi_fn! {
+    fn rure_rewrite(
+        rewrite: *const u8, 
+        length: size_t, 
+        vecs: *const *const u8, 
+        vecs_lengths: *const size_t, 
+        vecs_count: size_t
+    ) -> *const c_char {
+        // 获取rewrite
+        let rewrite = unsafe { slice::from_raw_parts(rewrite, length) };
+        let rewrite_str = std::str::from_utf8(rewrite).unwrap();
+        
+        //获取vecs中的内容
+        let (raw_vecs, raw_vecsl) = unsafe {
+            (
+                slice::from_raw_parts(vecs, vecs_count),
+                slice::from_raw_parts(vecs_lengths, vecs_count)
+            )
+        };
+
+        let mut rure_vecs = Vec::with_capacity(vecs_count);
+        for (&raw_vec, &raw_vecl) in raw_vecs.iter().zip(raw_vecsl) {
+            let rure_vec = unsafe { slice::from_raw_parts(raw_vec, raw_vecl) };
+            rure_vecs.push(str::from_utf8(rure_vec).unwrap());
+            // let elem = String::from_utf8(rure_vec).unwrap();;
+        }
+        for i in 0..rure_vecs.len() {
+            println!("{}, ", rure_vecs[i]);
+        }
+
+        let rewrite_chars = rewrite_str.chars().collect::<Vec<char>>();
+        let mut i = 0;
+        // let outl = unsafe { slice::from_raw_parts(rure_out, rure_out_len) };
+        // let mut out = std::str::from_utf8(outl).unwrap().to_string();
+
+        let mut out = String::new();
+        while i < rewrite_chars.len() {
+            if rewrite_chars[i] != '\\' {
+                out.push(rewrite_chars[i]);
+                i += 1;
+                continue;
+            }
+            i += 1;
+            let c = {
+                if i < rewrite_chars.len() {
+                    rewrite_chars[i]
+                } else {
+                    '~'
+                }
+            };
+            // let n
+            if c.is_ascii_digit() {
+                let n = c as usize - '0' as usize;
+                if n >= vecs_count {
+                    return ptr::null();
+                }
+                let elem = rure_vecs[n];
+                if !elem.is_empty() {
+                    out.push_str(elem);
+                }
+                i += 1; 
+            } else if rewrite_chars[i] == '\\' {
+                out.push('\\');
+                i += 1;
+            } else {
+                return ptr::null();
+            }
+        }
+        println!("{}", out);
+        // out.as_p
+        let out = match CString::new(out) {
+            Ok(val) => val,
+            Err(err) => {
+                println!("{}", err);
+                return ptr::null();
+            },
+        };
+        out.into_raw() as *const c_char
+    }
 }
\ No newline at end of file
-- 
Gitee