# HG changeset patch
# User Matti Hamalainen <ccr@tnsp.org>
# Date 1578411626 -7200
# Node ID 4cd67faadbd3cc1aafaacc8981f719f3175d04e8
# Parent  36226425aac136a90398287128102e9f6b1cbf77
Fix encoding and improve decoding of character set case (upper/lower) for two PETSCII formats. Also generalize the functions a bit.

diff -r 36226425aac1 -r 4cd67faadbd3 tools/lib64fmts.c
--- a/tools/lib64fmts.c	Tue Jan 07 15:25:14 2020 +0200
+++ b/tools/lib64fmts.c	Tue Jan 07 17:40:26 2020 +0200
@@ -103,21 +103,21 @@
 }
 
 
-static int fmtDecodeMarqPETSCIIData(const DMC64EncDecOp *op, DMC64Image *img,
+static int fmtDecodeHiresPETSCIICharsetData(const DMC64EncDecOp *op, DMC64Image *img,
     const DMGrowBuf *buf, const DMC64ImageCommonFormat *fmt)
 {
-    (void) op;
-    (void) buf;
     (void) fmt;
-
-    switch (img->extraData[0].data[0])
+    Uint8 val;
+
+    switch (buf->data[op->offs])
     {
-        case 20: img->extraInfo[D64_EI_CHAR_CASE] = 0; break; // upper case
-        case 23: img->extraInfo[D64_EI_CHAR_CASE] = 1; break; // lower case
+        case 0x14: val = 0; break; // upper case
+        case 0x17: val = 1; break; // lower case
         default:
             return DMERR_INVALID_DATA;
     }
 
+    img->extraInfo[D64_EI_CHAR_CASE] = val;
     img->extraInfo[D64_EI_MODE] = D64_FMT_HIRES | D64_FMT_CHAR;
     img->extraInfo[D64_EI_CHAR_CUSTOM] = 0;
 
@@ -125,22 +125,28 @@
 }
 
 
+static int fmtEncodeHiresPETSCIICharsetData(
+    const DMC64EncDecOp *op, DMGrowBuf *buf, const DMC64Image *img)
+{
+    Uint8 val;
+
+    switch (img->extraInfo[D64_EI_CHAR_CASE])
+    {
+        case 0: val = 0x14; break;
+        case 1: val = 0x17; break;
+        default: return DMERR_INVALID_DATA;
+    }
+
+    buf->data[op->offs + 2] = val;
+
+    return DMERR_OK;
+}
+
+
 static int fmtEncodeMarqPETSCIIData(const DMC64EncDecOp *op, DMGrowBuf *buf,
     const DMC64Image *img, const DMC64ImageCommonFormat *fmt)
 {
-    (void) op;
-    (void) img;
     (void) fmt;
-    Uint8 val;
-
-    switch (img->extraInfo[D64_EI_CHAR_CASE])
-    {
-        case 0: val = 20; break;
-        case 1: val = 23; break;
-        default: return DMERR_INVALID_DATA;
-    }
-
-    img->extraData[0].data[0] = val;
 
     memcpy(buf->data,
         fmtMarqPETSCII_ID1, sizeof(fmtMarqPETSCII_ID1));
@@ -151,7 +157,7 @@
     memcpy(buf->data + sizeof(fmtMarqPETSCII_ID1) + sizeof(fmtMarqPETSCII_ID2),
         fmtMarqPETSCII_ID3, sizeof(fmtMarqPETSCII_ID3));
 
-    return DMERR_OK;
+    return fmtEncodeHiresPETSCIICharsetData(op, buf, img);
 }
 
 
@@ -256,6 +262,7 @@
     0xad, 0x44, 0x0c, 0x8d, 0x18, 0xd0, 0x4c, 0x55, 0x08
 };
 
+
 static int fmtProbeCocaPETSCII(const DMGrowBuf *buf, const DMC64ImageFormat *fmt)
 {
     (void) fmt;
@@ -272,16 +279,12 @@
 static int fmtEncodeCocaPETSCIIData(const DMC64EncDecOp *op, DMGrowBuf *buf,
     const DMC64Image *img, const DMC64ImageCommonFormat *fmt)
 {
-    (void) op;
-    (void) img;
     (void) fmt;
 
     memcpy(buf->data,
         fmtCocaPETSCII_ID1, sizeof(fmtCocaPETSCII_ID1));
 
-    buf->data[0x0c44 - 0x0801 + 2] = 0x14;
-
-    return DMERR_OK;
+    return fmtEncodeHiresPETSCIICharsetData(op, buf, img);
 }
 
 
@@ -2757,13 +2760,12 @@
             NULL,
             {
                 // For offset values see petscii/m_c64.pde :: save_prg()
-                { DO_FUNC       , 0              , 0     , 0,  0,   0, NULL, fmtEncodeMarqPETSCIIData, DF_NORMAL },
+                { DO_FUNC       , 0              , 20 - 2, 0,  0,   0, NULL, fmtEncodeMarqPETSCIIData, DF_NORMAL },
                 { DO_COPY       , DS_SCREEN_RAM  , 0x60  , 0,  0,   0, NULL, NULL, DF_NORMAL },
                 { DO_COPY       , DS_COLOR_RAM   , 0x60 + 1000,0,0, 0, NULL, NULL, DF_NORMAL },
                 { DO_SET_MEM_LO , DS_D020        , 25 - 2, 0,  0,   0, NULL, NULL, DF_NORMAL },
                 { DO_SET_MEM_LO , DS_BGCOL       , 30 - 2, 0,  0,   0, NULL, NULL, DF_NORMAL },
-                { DO_COPY       , DS_EXTRA_DATA  , 20 - 2, 0,  1,   0, NULL, NULL, DF_NORMAL },
-                { DO_FUNC       , 0              , 0     , 0,  0,   0, fmtDecodeMarqPETSCIIData, NULL, DF_NORMAL },
+                { DO_FUNC       , 0              , 20 - 2, 0,  0,   0, fmtDecodeHiresPETSCIICharsetData, NULL, DF_NORMAL },
 
                 { DO_LAST       , 0              , 0     , 0,  0,   0, NULL, NULL, DF_NORMAL },
             }
@@ -2833,12 +2835,13 @@
             NULL, NULL,
             NULL,
             {
-                { DO_FUNC       , 0              , 0     , 0,  0,   0, NULL, fmtEncodeCocaPETSCIIData, DF_NORMAL },
+                { DO_FUNC       , 0              , 0x0c44 - 0x0801, 0,  0,   0, NULL, fmtEncodeCocaPETSCIIData, DF_NORMAL },
                 { DO_COPY       , DS_SCREEN_RAM  , 0x085a - 0x0801, 0,  0,   0, NULL, NULL, DF_NORMAL },
                 { DO_COPY       , DS_COLOR_RAM   , 0x0c5a - 0x0801, 0,  0,   0, NULL, NULL, DF_NORMAL },
 
                 { DO_SET_MEM_LO , DS_D020        , 0x0c42 - 0x0801, 0,  0,   0, NULL, NULL, DF_NORMAL },
                 { DO_SET_MEM_LO , DS_BGCOL       , 0x0c43 - 0x0801, 0,  0,   0, NULL, NULL, DF_NORMAL },
+                { DO_FUNC       , 0              , 0x0c44 - 0x0801, 0,  0,   0, fmtDecodeHiresPETSCIICharsetData, NULL, DF_NORMAL },
 
                 { DO_LAST       , 0              , 0     , 0,  0,   0, NULL, NULL, DF_NORMAL },
             }