Add support for append statements

README.md

@@ -64,7 +64,7 @@ The following QuickBMS commands are currently supported by the langauge server.
 * [ ] `PutVarChr VAR OFFSET VAR [TYPE]`
 * [ ] `Debug [MODE]`
 * [ ] `Padding VAR [FILENUM] [BASE_OFF]`
-* [ ] `Append [DIRECTION]`
+* [x] `Append [DIRECTION]`
 * [x] `Encryption ALGO KEY [IVEC] [MODE] [KEYLEN]`
 * [x] `Print MESSAGE`
 * [x] `GetArray VAR ARRAY VAR_IDX`

src/server/keyword_docs/append.txt

@@ -0,0 +1,54 @@
+Append [DIRECTION]
+
+    Command to enable the append mode in the *Log commands, so if
+    the output filename already exists it will not be overwritten,
+    the new content is concatenated (appended) to the existent one.
+    Note that with real files (not memory files) the user may be
+    prompted before writing the output file if it already existed
+    before the running of the script.
+    Note that the reimport mode may not work correctly when you use
+    a combo of MEMORY_FILE and Append, so the direct and more
+    simple Log to file + Append is suggested.
+    Note that from QuickBMS 0.11 the Append command also affects
+    the Put* commands (Put/PutDString/PutCT).
+
+    Arguments:
+      DIRECTION This is a new optional argument that allows to
+                specify where placing the new content:
+                -1  prefix:
+                    a negative value means that the new content
+                    will be placed before the current file, so the
+                    old content will be appended to the new one
+                0   append:
+                    the new content will be appended to the current
+                    one (default, just like without DIRECTION)
+                1   overwrite:
+                    the new content will overwrite the current one
+                    without changing the file size if the new one
+                    is smaller, use goto to set the offset where
+                    placing the new content.
+                2   insert:
+                    the new content will be inserted in the current
+                    position (size = position + data + remaining)
+
+    Examples:
+      append
+      Log "dump.dat" 0 0x10
+      Log "dump.dat" 0x10 0x100
+
+    The following is a particular example for allocating a
+    MEMORY_FILE and using it instead of TEMPORARY_FILE saving space
+    on the disk and performances:
+
+      math TMP = CHUNKS
+      math TMP *= 0x8000
+      log MEMORY_FILE 0 0
+      putvarchr MEMORY_FILE TMP 0   # pre-allocation for speed
+      log MEMORY_FILE 0 0           # reset the position and size
+      append
+      for i = 0 < CHUNKS
+          ...
+          clog MEMORY_FILE OFFSET ZSIZE 0x8000
+      next i
+      append
+      get SIZE asize MEMORY_FILE

src/server/state.rs

@@ -456,6 +456,10 @@ pub fn get_keyword_docs() -> HashMap<String, String> {
             "filexor".to_string(),
             include_str!("keyword_docs/filexor.txt").to_string(),
         ),
+        (
+            "append".to_string(),
+            include_str!("keyword_docs/append.txt").to_string(),
+        ),
     ]
     .iter()
     .cloned()

tree-sitter-quickbms/grammar.js

@@ -42,6 +42,7 @@ module.exports = grammar({
       $.reverselong_statement,
       $.reverselonglong_statement,
       $.filexor_statement,
+      $.append_statement,
     ),
     set_statement: $ => seq(
       $.set,
@@ -220,6 +221,10 @@ module.exports = grammar({
       field("offset", optional($._expression)),
       // field("file_number", optional($._expression)),
     ),
+    append_statement: $ => seq(
+      $.append,
+      field("direction", optional(choice("-1", "0", "1", "2"))),
+    ),
     comparison: $ => choice(
       "<",
       ">",
@@ -329,6 +334,7 @@ module.exports = grammar({
     reverselong: $ => /[Rr][Ee][Vv][Ee][Rr][Ss][Ee][Ll][Oo][Nn][Gg]/,
     reverselonglong: $ => /[Rr][Ee][Vv][Ee][Rr][Ss][Ee][Ll][Oo][Nn][Gg][Ll][Oo][Nn][Gg]/,
     filexor: $ => /[Ff][Ii][Ll][Ee][Xx][Oo][Rr]/,
+    append: $ => /[Aa][Pp][Pp][Ee][Nn][Dd]/,
     question_mark: $ => /\?/,
 
     identifier: $ => /[a-zA-Z_\\]+[a-zA-Z0-9_\-\\]*/,

tree-sitter-quickbms/test/corpus/append.bms

@@ -0,0 +1,35 @@
+================================================================================
+Append statements
+================================================================================
+
+append
+Log "dump.dat" 0 0x10
+Log "dump.dat" 0x10 0x100
+append -1
+append 0
+append 1
+append 2
+
+--------------------------------------------------------------------------------
+
+(source_file
+  (append_statement
+    (append))
+  (log_statement
+    (log)
+    (string_literal)
+    (integer_literal)
+    (integer_literal))
+  (log_statement
+    (log)
+    (string_literal)
+    (integer_literal)
+    (integer_literal))
+  (append_statement
+    (append))
+  (append_statement
+    (append))
+  (append_statement
+    (append))
+  (append_statement
+    (append)))

tree-sitter-quickbms/test/corpus/log.bms

@@ -8,6 +8,7 @@ Log "dump.dat" 0 SIZE
 Log "" 0 SIZE
 Log "folder/name.*" 0 SIZE
 Log "redecrypted_file.dat" 0 SIZE MEMORY_FILE
+Log "dump.dat" 0 0x10
 
 --------------------------------------------------------------------------------
 
@@ -42,4 +43,9 @@ Log "redecrypted_file.dat" 0 SIZE MEMORY_FILE
     (string_literal)
     (integer_literal)
     (identifier)
-    (identifier)))
+    (identifier))
+  (log_statement
+    (log)
+    (string_literal)
+    (integer_literal)
+    (integer_literal)))