Merge functions since there are no more options

Author: groves

helix-view/src/base64/mod.rs

@@ -1,86 +1,37 @@
 use std::ops::{BitAnd, BitOr, Shl, Shr};
 
-pub fn encode<T: AsRef<[u8]>>(input: T) -> String {
-    let encoded_size =
-        encoded_len(input.as_ref().len()).expect("integer overflow when calculating buffer size");
-    let mut buf = vec![0; encoded_size];
-
-    encode_with_padding(input.as_ref(), &mut buf[..], encoded_size);
-
-    String::from_utf8(buf).expect("Invalid UTF8")
-}
-
-pub fn encoded_len(bytes_len: usize) -> Option<usize> {
-    let rem = bytes_len % 3;
-
-    let complete_input_chunks = bytes_len / 3;
-    let complete_chunk_output = complete_input_chunks.checked_mul(4);
-
-    if rem > 0 {
-        complete_chunk_output.and_then(|c| c.checked_add(4))
-    } else {
-        complete_chunk_output
-    }
-}
-
-fn encode_with_padding(input: &[u8], output: &mut [u8], expected_encoded_size: usize) {
-    debug_assert_eq!(expected_encoded_size, output.len());
-
-    let b64_bytes_written = encode_bytes(input, output);
-
-    let padding_bytes = add_padding(input.len(), &mut output[b64_bytes_written..]);
-
-    let encoded_bytes = b64_bytes_written
-        .checked_add(padding_bytes)
-        .expect("usize overflow when calculating b64 length");
-
-    debug_assert_eq!(expected_encoded_size, encoded_bytes);
-}
-
-pub fn add_padding(input_len: usize, output: &mut [u8]) -> usize {
-    // TODO base on encoded len to use cheaper mod by 4 (aka & 7)
-    let rem = input_len % 3;
-    let mut bytes_written = 0;
-    for _ in 0..((3 - rem) % 3) {
-        output[bytes_written] = PAD_BYTE;
-        bytes_written += 1;
-    }
-
-    bytes_written
-}
 const PAD_BYTE: u8 = b'=';
 const ENCODE_TABLE: &[u8] =
     "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/".as_bytes();
+const LOW_SIX_BITS: u32 = 0x3F;
 
-fn encode_bytes(input: &[u8], output: &mut [u8]) -> usize {
-    // complete chunks first
+pub fn encode(input: &[u8]) -> String {
+    let rem = input.len() % 3;
+    let complete_chunks = input.len() / 3;
+    let remainder_chunk = if rem == 0 { 0 } else { 1 };
+    let encoded_size = (complete_chunks + remainder_chunk) * 4;
 
-    const LOW_SIX_BITS: u32 = 0x3F;
+    let mut output = vec![0; encoded_size];
 
-    let rem = input.len() % 3;
-    // will never underflow
+    // complete chunks first
     let complete_chunk_len = input.len() - rem;
 
     let mut input_index = 0_usize;
     let mut output_index = 0_usize;
-    if let Some(last_complete_chunk_index) = complete_chunk_len.checked_sub(3) {
-        while input_index <= last_complete_chunk_index {
-            let chunk = &input[input_index..input_index + 3];
-
-            // populate low 24 bits from 3 bytes
-            let chunk_int: u32 =
-                (chunk[0] as u32).shl(16) | (chunk[1] as u32).shl(8) | (chunk[2] as u32);
-            // encode 4x 6-bit output bytes
-            output[output_index] = ENCODE_TABLE[chunk_int.shr(18) as usize];
-            output[output_index + 1] =
-                ENCODE_TABLE[chunk_int.shr(12_u8).bitand(LOW_SIX_BITS) as usize];
-            output[output_index + 2] =
-                ENCODE_TABLE[chunk_int.shr(6_u8).bitand(LOW_SIX_BITS) as usize];
-            output[output_index + 3] = ENCODE_TABLE[chunk_int.bitand(LOW_SIX_BITS) as usize];
-
-            input_index += 3;
-            output_index += 4;
-        }
+    while input_index < complete_chunk_len {
+        let chunk = &input[input_index..input_index + 3];
+
+        // populate low 24 bits from 3 bytes
+        let chunk_int: u32 =
+            (chunk[0] as u32).shl(16) | (chunk[1] as u32).shl(8) | (chunk[2] as u32);
+        // encode 4x 6-bit output bytes
+        output[output_index] = ENCODE_TABLE[chunk_int.shr(18) as usize];
+        output[output_index + 1] = ENCODE_TABLE[chunk_int.shr(12_u8).bitand(LOW_SIX_BITS) as usize];
+        output[output_index + 2] = ENCODE_TABLE[chunk_int.shr(6_u8).bitand(LOW_SIX_BITS) as usize];
+        output[output_index + 3] = ENCODE_TABLE[chunk_int.bitand(LOW_SIX_BITS) as usize];
+
+        input_index += 3;
+        output_index += 4;
     }
 
     // then leftovers
@@ -95,17 +46,16 @@ fn encode_bytes(input: &[u8], output: &mut [u8]) -> usize {
         // bottom 4 bits of [1], with the 2 bottom bits as zero
         output[output_index + 2] =
             ENCODE_TABLE[(chunk[1].shl(2_u8) as u32).bitand(LOW_SIX_BITS) as usize];
-
-        output_index += 3;
+        output[output_index + 3] = PAD_BYTE;
     } else if rem == 1 {
         let byte = input[input_index];
         output[output_index] = ENCODE_TABLE[byte.shr(2) as usize];
         output[output_index + 1] =
             ENCODE_TABLE[(byte.shl(4_u8) as u32).bitand(LOW_SIX_BITS) as usize];
-        output_index += 2;
+        output[output_index + 2] = PAD_BYTE;
+        output[output_index + 3] = PAD_BYTE;
     }
-
-    output_index
+    String::from_utf8(output).expect("Invalid UTF8")
 }
 
 #[cfg(test)]

helix-view/src/clipboard.rs

@@ -159,7 +159,7 @@ mod provider {
         impl SetClipboardCommand {
             pub fn new(content: &str, clipboard_type: ClipboardType) -> Self {
                 Self {
-                    encoded_content: base64::encode(content),
+                    encoded_content: base64::encode(content.as_bytes()),
                     clipboard_type,
                 }
             }