Adding memory card support to psyqo

src/mips/common/util/gen-sjis-encode-table.py

@@ -0,0 +1,51 @@
+#!/usr/bin/env python3
+# Regenerates sjis-encode-table.h: the inverse of sjis-table.h (Unicode -> Shift-JIS).
+# The forward table is indexed by a remapped Shift-JIS codepoint (single bytes at
+# 0x000-0x0ff; lead 0x80-0x8f at base 0x100; lead 0x90-0x9f at base 0x1100;
+# lead 0xe0-0xef at base 0x2100; index = base + ((lead & 0xf) << 8) + trail).
+# We walk every forward entry, reconstruct its Shift-JIS bytes, and keep the
+# lowest Shift-JIS code per Unicode value (so single-byte forms win over
+# double-byte). Run from the repo root.
+import re, sys
+
+fwd = [int(x, 16) for x in
+       re.findall(r'0x[0-9a-fA-F]{4}', open('src/mips/common/util/sjis-table.h').read())]
+
+def index_to_sjis(index):
+    if index < 0x100:
+        return index
+    if index < 0x1100:   base, lead_hi = 0x100,  0x80
+    elif index < 0x2100: base, lead_hi = 0x1100, 0x90
+    else:                base, lead_hi = 0x2100, 0xe0
+    r = index - base
+    return ((lead_hi | (r >> 8)) << 8) | (r & 0xff)
+
+rev = {}
+for index, uni in enumerate(fwd):
+    sjis = index_to_sjis(index)
+    if sjis >= 0x100:
+        if uni == 0x0020:  # unmapped filler cells decode to space; skip them
+            continue
+        trail = sjis & 0xff
+        if not (0x40 <= trail <= 0x7e or 0x80 <= trail <= 0xfc):
+            continue
+    rev.setdefault(uni, sjis)
+
+items = sorted(rev.items())
+with open('src/mips/common/util/sjis-encode-table.h', 'w') as f:
+    f.write("#pragma once\n\n#include <stdint.h>\n\n")
+    f.write("// Generated by gen-sjis-encode-table.py: the inverse of sjis-table.h.\n")
+    f.write("// Each index maps a Unicode codepoint to its Shift-JIS encoding. The list is\n")
+    f.write("// sorted by Unicode value for binary search. A Shift-JIS value <= 0xff is a\n")
+    f.write("// single byte; otherwise it is two bytes, high byte first.\n\n")
+    f.write("static const struct {\n    uint16_t unicode;\n    uint16_t sjis;\n} c_unicodeToSjisConvTable[] = {\n")
+    line = "    "
+    for uni, sjis in items:
+        tok = "{0x%04x, 0x%04x}, " % (uni, sjis)
+        if len(line) + len(tok) > 116:
+            f.write(line.rstrip() + "\n"); line = "    "
+        line += tok
+    if line.strip():
+        f.write(line.rstrip() + "\n")
+    f.write("};\n")
+print("emitted %d entries" % len(items), file=sys.stderr)

src/mips/common/util/sjis-encode.h

@@ -0,0 +1,115 @@
+#pragma once
+
+#include <stdint.h>
+
+#include "common/util/sjis-encode-table.h"
+
+// Unicode -> Shift-JIS encoding, the inverse of support/sjis_conv.cc's decoder.
+// Shares the same data as the forward table (sjis-table.h), inverted into
+// sjis-encode-table.h. Usable from both the host and the MIPS targets.
+
+namespace Sjis {
+
+// Returns the Shift-JIS encoding of a Unicode codepoint, or 0 if it has no
+// mapping. A result <= 0xff is a single byte; otherwise it is two bytes, high
+// byte first. (U+0000 also returns 0, which is harmless for string use.)
+static inline uint16_t unicodeToSjis(uint16_t unicode) {
+    unsigned lo = 0, hi = sizeof(c_unicodeToSjisConvTable) / sizeof(c_unicodeToSjisConvTable[0]);
+    while (lo < hi) {
+        unsigned mid = (lo + hi) / 2;
+        uint16_t u = c_unicodeToSjisConvTable[mid].unicode;
+        if (u == unicode) return c_unicodeToSjisConvTable[mid].sjis;
+        if (u < unicode) {
+            lo = mid + 1;
+        } else {
+            hi = mid;
+        }
+    }
+    return 0;
+}
+
+// Decodes one UTF-8 codepoint from str, advancing *index. Returns the codepoint,
+// or 0xfffd (replacement) on a malformed sequence. Codepoints above the BMP are
+// returned truncated to 0xfffd since Shift-JIS cannot represent them.
+static inline uint16_t utf8Decode(const char* str, uint32_t length, uint32_t* index) {
+    uint32_t i = *index;
+    uint8_t c = str[i++];
+    uint32_t cp;
+    unsigned extra;
+    if (c < 0x80) {
+        *index = i;
+        return c;
+    } else if ((c & 0xe0) == 0xc0) {
+        cp = c & 0x1f;
+        extra = 1;
+    } else if ((c & 0xf0) == 0xe0) {
+        cp = c & 0x0f;
+        extra = 2;
+    } else {
+        *index = i;
+        return 0xfffd;
+    }
+    for (unsigned k = 0; k < extra; k++) {
+        if (i >= length || (str[i] & 0xc0) != 0x80) {
+            *index = i;
+            return 0xfffd;
+        }
+        cp = (cp << 6) | (str[i++] & 0x3f);
+    }
+    *index = i;
+    return cp > 0xffff ? 0xfffd : (uint16_t)cp;
+}
+
+// Encodes a UTF-8 C string to Shift-JIS. Writes up to dstSize bytes and returns
+// the number written. Codepoints with no Shift-JIS mapping are emitted as '?'.
+// The output is not NUL-terminated.
+static inline uint32_t utf8ToSjis(uint8_t* dst, uint32_t dstSize, const char* src) {
+    uint32_t srcLen = 0;
+    while (src[srcLen]) srcLen++;
+    uint32_t in = 0, out = 0;
+    while (in < srcLen && out < dstSize) {
+        uint16_t cp = utf8Decode(src, srcLen, &in);
+        uint16_t sjis = unicodeToSjis(cp);
+        if (sjis == 0 && cp != 0) sjis = '?';
+        if (sjis > 0xff) {
+            if (out + 2 > dstSize) break;
+            dst[out++] = sjis >> 8;
+            dst[out++] = sjis & 0xff;
+        } else {
+            dst[out++] = sjis & 0xff;
+        }
+    }
+    return out;
+}
+
+// Encodes a UTF-8 string to Shift-JIS using the BIOS save-title convention:
+// printable ASCII is promoted to its fullwidth form (space -> U+3000,
+// 0x21..0x7e -> U+ff01..U+ff5e) so it renders in the manager's fullwidth font,
+// while any non-ASCII codepoint (e.g. Japanese) is encoded directly. This is
+// what memory card save titles want. Writes up to dstSize bytes, returns the
+// number written; output is not NUL-terminated.
+static inline uint32_t utf8ToSjisTitle(uint8_t* dst, uint32_t dstSize, const char* src) {
+    uint32_t srcLen = 0;
+    while (src[srcLen]) srcLen++;
+    uint32_t in = 0, out = 0;
+    while (in < srcLen && out < dstSize) {
+        uint16_t cp = utf8Decode(src, srcLen, &in);
+        if (cp == ' ') {
+            cp = 0x3000;
+        } else if (cp >= 0x21 && cp <= 0x7e) {
+            cp = 0xff00 + (cp - 0x20);
+        }
+        uint16_t sjis = unicodeToSjis(cp);
+        if (sjis == 0 && cp != 0) sjis = '?';
+        if (sjis > 0xff) {
+            if (out + 2 > dstSize) break;
+            dst[out++] = sjis >> 8;
+            dst[out++] = sjis & 0xff;
+        } else {
+            dst[out++] = sjis & 0xff;
+        }
+    }
+    return out;
+}
+
+}  // namespace Sjis

src/mips/psyqo/examples/memorycard/Makefile

@@ -0,0 +1,12 @@
+TARGET = memorycard
+TYPE = ps-exe
+
+SRCS = \
+memorycard.cpp \
+
+ifeq ($(TEST),true)
+CPPFLAGS = -Werror
+endif
+CXXFLAGS = -std=c++20
+
+include ../../psyqo.mk