efi_loader: carve out utf_to_cp()

Carve out a function to translate a Unicode code point to an 8bit codepage.

Provide a unit test for the new function.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>

diff --git a/include/charset.h b/include/charset.h
index 64ba91f..52e7d14 100644 (file)
--- a/include/charset.h
+++ b/include/charset.h
@@ -275,4 +275,15 @@ u16 *u16_strdup(const void *src);
  */
 uint8_t *utf16_to_utf8(uint8_t *dest, const uint16_t *src, size_t size);
 
+/**
+ * utf_to_cp() - translate Unicode code point to 8bit codepage
+ *
+ * Codepoints that do not exist in the codepage are rendered as question mark.
+ *
+ * @c:         pointer to Unicode code point to be translated
+ * @codepage:  Unicode to codepage translation table
+ * Return:     0 on success, -ENOENT if codepoint cannot be translated
+ */
+int utf_to_cp(s32 *c, const u16 *codepage);
+
 #endif /* __CHARSET_H_ */

diff --git a/lib/charset.c b/lib/charset.c
index 814847d..1345c8f 100644 (file)
--- a/lib/charset.c
+++ b/lib/charset.c
@@ -10,6 +10,7 @@
 #include <capitalization.h>
 #include <cp437.h>
 #include <efi_loader.h>
+#include <errno.h>
 #include <malloc.h>
 
 /**
@@ -472,3 +473,30 @@ uint8_t *utf16_to_utf8(uint8_t *dest, const uint16_t *src, size_t size)
 
        return dest;
 }
+
+/**
+ * utf_to_cp() - translate Unicode code point to 8bit codepage
+ *
+ * Codepoints that do not exist in the codepage are rendered as question mark.
+ *
+ * @c:         pointer to Unicode code point to be translated
+ * @codepage:  Unicode to codepage translation table
+ * Return:     0 on success, -ENOENT if codepoint cannot be translated
+ */
+int utf_to_cp(s32 *c, const u16 *codepage)
+{
+       if (*c >= 0x80) {
+               int j;
+
+               /* Look up codepage translation */
+               for (j = 0; j < 0x80; ++j) {
+                       if (*c == codepage[j]) {
+                               *c = j + 0x80;
+                               return 0;
+                       }
+               }
+               *c = '?';
+               return -ENOENT;
+       }
+       return 0;
+}

diff --git a/lib/efi_loader/efi_unicode_collation.c b/lib/efi_loader/efi_unicode_collation.c
index bf5314c..36be798 100644 (file)
--- a/lib/efi_loader/efi_unicode_collation.c
+++ b/lib/efi_loader/efi_unicode_collation.c
@@ -300,23 +300,10 @@ static bool EFIAPI efi_str_to_fat(struct efi_unicode_collation_protocol *this,
                        break;
                }
                c = utf_to_upper(c);
-               if (c >= 0x80) {
-                       int j;
-
-                       /* Look for codepage translation */
-                       for (j = 0; j < 0x80; ++j) {
-                               if (c == codepage[j]) {
-                                       c = j + 0x80;
-                                       break;
-                               }
-                       }
-                       if (j >= 0x80) {
-                               c = '_';
-                               ret = true;
-                       }
-               } else if (c && (c < 0x20 || strchr(illegal, c))) {
-                       c = '_';
+               if (utf_to_cp(&c, codepage) ||
+                   (c && (c < 0x20 || strchr(illegal, c)))) {
                        ret = true;
+                       c = '_';
                }
 
                fat[i] = c;

diff --git a/test/unicode_ut.c b/test/unicode_ut.c
index 6130ef0..2cc6b5f 100644 (file)
--- a/test/unicode_ut.c
+++ b/test/unicode_ut.c
@@ -595,6 +595,35 @@ static int unicode_test_u16_strsize(struct unit_test_state *uts)
 }
 UNICODE_TEST(unicode_test_u16_strsize);
 
+static int unicode_test_utf_to_cp(struct unit_test_state *uts)
+{
+       int ret;
+       s32 c;
+
+       c = '\n';
+       ret = utf_to_cp(&c, codepage_437);
+       ut_asserteq(0, ret);
+       ut_asserteq('\n', c);
+
+       c = 'a';
+       ret = utf_to_cp(&c, codepage_437);
+       ut_asserteq(0, ret);
+       ut_asserteq('a', c);
+
+       c = 0x03c4; /* Greek small letter tau */
+       ret = utf_to_cp(&c, codepage_437);
+       ut_asserteq(0, ret);
+       ut_asserteq(0xe7, c);
+
+       c = 0x03a4; /* Greek capital letter tau */
+       ret = utf_to_cp(&c, codepage_437);
+       ut_asserteq(-ENOENT, ret);
+       ut_asserteq('?', c);
+
+       return 0;
+}
+UNICODE_TEST(unicode_test_utf_to_cp);
+
 #ifdef CONFIG_EFI_LOADER
 static int unicode_test_efi_create_indexed_name(struct unit_test_state *uts)
 {