From b72b71fd51e633cb7a63d9f1883266b3d4acac11 Mon Sep 17 00:00:00 2001
From: Olly Betts <olly@survex.com>
Date: Thu, 21 Nov 2024 08:38:41 +1300
Subject: [PATCH] Factor out duplicate code for writing 4 hex digits

---
 compiler/generator.c        |  8 ++++++++
 compiler/generator_csharp.c | 17 ++---------------
 compiler/generator_go.c     | 17 ++---------------
 compiler/generator_java.c   | 17 ++---------------
 compiler/generator_js.c     | 17 ++---------------
 compiler/generator_python.c | 17 ++---------------
 compiler/generator_rust.c   | 19 +++----------------
 compiler/header.h           |  1 +
 8 files changed, 22 insertions(+), 91 deletions(-)

diff --git a/compiler/generator.c b/compiler/generator.c
index 5c78e304..bc67f34f 100644
--- a/compiler/generator.c
+++ b/compiler/generator.c
@@ -77,6 +77,14 @@ static void write_hexdigit(struct generator * g, int i) {
     str_append_ch(g->outbuf, "0123456789ABCDEF"[i & 0xF]); /* hexchar */
 }
 
+extern void write_hex4(struct generator * g, int ch) {
+    int i;
+    for (i = 0; i < 4; ++i) {
+        write_hexdigit(g, ch);
+        ch >>= 4;
+    }
+}
+
 static void write_hex(struct generator * g, int i) {
     if (i >> 4) write_hex(g, i >> 4);
     write_hexdigit(g, i); /* hex integer */
diff --git a/compiler/generator_csharp.c b/compiler/generator_csharp.c
index 151f85e3..7e53f480 100644
--- a/compiler/generator_csharp.c
+++ b/compiler/generator_csharp.c
@@ -43,20 +43,6 @@ static void write_varref(struct generator * g, struct name * p) {
     write_varname(g, p);
 }
 
-static void write_hexdigit(struct generator * g, int n) {
-
-    write_char(g, n < 10 ? n + '0' : n - 10 + 'A');
-}
-
-static void write_hex(struct generator * g, int ch) {
-
-    write_string(g, "\\u");
-    {
-        int i;
-        for (i = 12; i >= 0; i -= 4) write_hexdigit(g, ch >> i & 0xf);
-    }
-}
-
 static void write_literal_string(struct generator * g, symbol * p) {
 
     int i;
@@ -67,7 +53,8 @@ static void write_literal_string(struct generator * g, symbol * p) {
             if (ch == '\"' || ch == '\\') write_string(g, "\\");
             write_char(g, ch);
         } else {
-            write_hex(g, ch);
+            write_string(g, "\\u");
+            write_hex4(g, ch);
         }
     }
     write_string(g, "\"");
diff --git a/compiler/generator_go.c b/compiler/generator_go.c
index 0da71689..5268fda3 100644
--- a/compiler/generator_go.c
+++ b/compiler/generator_go.c
@@ -53,20 +53,6 @@ static void write_varref(struct generator * g, struct name * p) {
     write_varname(g, p);
 }
 
-static void write_hexdigit(struct generator * g, int n) {
-
-    write_char(g, n < 10 ? n + '0' : n - 10 + 'A');
-}
-
-static void write_hex(struct generator * g, int ch) {
-
-    write_string(g, "\\u");
-    {
-        int i;
-        for (i = 12; i >= 0; i -= 4) write_hexdigit(g, ch >> i & 0xf);
-    }
-}
-
 static void write_literal_string(struct generator * g, symbol * p) {
 
     int i = 0;
@@ -78,7 +64,8 @@ static void write_literal_string(struct generator * g, symbol * p) {
             if (ch == '\"' || ch == '\\') write_string(g, "\\");
             write_char(g, ch);
         } else {
-            write_hex(g, ch);
+            write_string(g, "\\u");
+            write_hex4(g, ch);
         }
     }
     write_string(g, "\"");
diff --git a/compiler/generator_java.c b/compiler/generator_java.c
index a0940d7c..c1aa6fd3 100644
--- a/compiler/generator_java.c
+++ b/compiler/generator_java.c
@@ -43,20 +43,6 @@ static void write_varref(struct generator * g, struct name * p) {
     write_varname(g, p);
 }
 
-static void write_hexdigit(struct generator * g, int n) {
-
-    write_char(g, n < 10 ? n + '0' : n - 10 + 'A');
-}
-
-static void write_hex(struct generator * g, int ch) {
-
-    write_string(g, "\\u");
-    {
-        int i;
-        for (i = 12; i >= 0; i -= 4) write_hexdigit(g, ch >> i & 0xf);
-    }
-}
-
 static void write_literal_string(struct generator * g, symbol * p) {
 
     int i;
@@ -67,7 +53,8 @@ static void write_literal_string(struct generator * g, symbol * p) {
             if (ch == '\"' || ch == '\\') write_string(g, "\\");
             write_char(g, ch);
         } else {
-            write_hex(g, ch);
+            write_string(g, "\\u");
+            write_hex4(g, ch);
         }
     }
     write_string(g, "\"");
diff --git a/compiler/generator_js.c b/compiler/generator_js.c
index d5ed27b6..a8159956 100644
--- a/compiler/generator_js.c
+++ b/compiler/generator_js.c
@@ -41,20 +41,6 @@ static void write_varref(struct generator * g, struct name * p) {
     write_varname(g, p);
 }
 
-static void write_hexdigit(struct generator * g, int n) {
-
-    write_char(g, n < 10 ? n + '0' : n - 10 + 'A');
-}
-
-static void write_hex(struct generator * g, int ch) {
-
-    write_string(g, "\\u");
-    {
-        int i;
-        for (i = 12; i >= 0; i -= 4) write_hexdigit(g, ch >> i & 0xf);
-    }
-}
-
 static void write_literal_string(struct generator * g, symbol * p) {
 
     int i;
@@ -65,7 +51,8 @@ static void write_literal_string(struct generator * g, symbol * p) {
             if (ch == '\"' || ch == '\\') write_string(g, "\\");
             write_char(g, ch);
         } else {
-            write_hex(g, ch);
+            write_string(g, "\\u");
+            write_hex4(g, ch);
         }
     }
     write_string(g, "\"");
diff --git a/compiler/generator_python.c b/compiler/generator_python.c
index b4b0755b..b7f87272 100644
--- a/compiler/generator_python.c
+++ b/compiler/generator_python.c
@@ -53,20 +53,6 @@ static void write_varref(struct generator * g, struct name * p) {
     write_varname(g, p);
 }
 
-static void write_hexdigit(struct generator * g, int n) {
-
-    write_char(g, n < 10 ? n + '0' : n - 10 + 'A');
-}
-
-static void write_hex(struct generator * g, int ch) {
-
-    write_string(g, "\\u");
-    {
-        int i;
-        for (i = 12; i >= 0; i -= 4) write_hexdigit(g, ch >> i & 0xf);
-    }
-}
-
 static void write_literal_string(struct generator * g, symbol * p) {
 
     int i;
@@ -77,7 +63,8 @@ static void write_literal_string(struct generator * g, symbol * p) {
             if (ch == '\"' || ch == '\\') write_string(g, "\\");
             write_char(g, ch);
         } else {
-            write_hex(g, ch);
+            write_string(g, "\\u");
+            write_hex4(g, ch);
         }
     }
     write_string(g, "\"");
diff --git a/compiler/generator_rust.c b/compiler/generator_rust.c
index bdd63285..924d1830 100644
--- a/compiler/generator_rust.c
+++ b/compiler/generator_rust.c
@@ -47,21 +47,6 @@ static void write_varref(struct generator * g, struct name * p) {
     write_varname(g, p);
 }
 
-static void write_hexdigit(struct generator * g, int n) {
-
-    write_char(g, n < 10 ? n + '0' : n - 10 + 'A');
-}
-
-static void write_hex(struct generator * g, int ch) {
-
-    write_string(g, "\\u{");
-    {
-        int i;
-        for (i = 12; i >= 0; i -= 4) write_hexdigit(g, ch >> i & 0xf);
-    }
-    write_string(g, "}");
-}
-
 static void write_literal_string(struct generator * g, symbol * p) {
 
     int i = 0;
@@ -73,7 +58,9 @@ static void write_literal_string(struct generator * g, symbol * p) {
             if (ch == '\"' || ch == '\\') write_string(g, "\\");
             write_char(g, ch);
         } else {
-            write_hex(g, ch);
+            write_string(g, "\\u{");
+            write_hex4(g, ch);
+            write_string(g, "}");
         }
     }
     write_string(g, "\"");
diff --git a/compiler/header.h b/compiler/header.h
index 3bc845ce..88efcfc9 100644
--- a/compiler/header.h
+++ b/compiler/header.h
@@ -411,6 +411,7 @@ extern void write_char(struct generator * g, int ch);
 extern void write_newline(struct generator * g);
 extern void write_string(struct generator * g, const char * s);
 extern void write_int(struct generator * g, int i);
+extern void write_hex4(struct generator * g, int ch);
 extern void write_symbol(struct generator * g, symbol s);
 extern void write_s(struct generator * g, const byte * b);
 extern void write_str(struct generator * g, struct str * str);