Windows 98 'support'

crt_win32.cpp

@@ -0,0 +1,167 @@
+/* Freestanding startup for the Pentium / Office XP host-floor x86 build.
+   Linked with -nostdlib so libgcc, libstdc++, and the MinGW CRT stay out. */
+
+#include <windows.h>
+
+extern int main(int argc, char** argv);
+
+typedef void (*xpmgr_ctor)(void);
+
+extern "C" xpmgr_ctor __init_array_start[] __attribute__((weak));
+extern "C" xpmgr_ctor __init_array_end[] __attribute__((weak));
+
+extern "C" void* memset(void* dst, int value, size_t count) {
+    unsigned char* bytes = (unsigned char*)dst;
+    unsigned char fill = (unsigned char)value;
+    while (count--) {
+        *bytes++ = fill;
+    }
+    return dst;
+}
+
+extern "C" void* memcpy(void* dst, const void* src, size_t count) {
+    unsigned char* out = (unsigned char*)dst;
+    const unsigned char* in = (const unsigned char*)src;
+    while (count--) {
+        *out++ = *in++;
+    }
+    return dst;
+}
+
+extern "C" void* memmove(void* dst, const void* src, size_t count) {
+    unsigned char* out = (unsigned char*)dst;
+    const unsigned char* in = (const unsigned char*)src;
+    size_t index;
+    if (out == in || count == 0) {
+        return dst;
+    }
+    if (out < in) {
+        for (index = 0; index < count; index++) {
+            out[index] = in[index];
+        }
+    } else {
+        index = count;
+        while (index > 0) {
+            index--;
+            out[index] = in[index];
+        }
+    }
+    return dst;
+}
+
+extern "C" int memcmp(const void* left, const void* right, size_t count) {
+    const unsigned char* a = (const unsigned char*)left;
+    const unsigned char* b = (const unsigned char*)right;
+    while (count--) {
+        if (*a != *b) {
+            return *a - *b;
+        }
+        a++;
+        b++;
+    }
+    return 0;
+}
+
+/* GCC calls this when a frame is at least one page. EAX is the frame size
+   and must be preserved; the caller subtracts it from ESP afterwards. */
+extern "C" __attribute__((naked)) void __chkstk_ms(void) {
+    __asm__ __volatile__(
+        "pushl %ecx\n\t"
+        "pushl %eax\n\t"
+        "cmpl $0x1000, %eax\n\t"
+        "leal 12(%esp), %ecx\n\t"
+        "jb 1f\n\t"
+        "2:\n\t"
+        "subl $0x1000, %ecx\n\t"
+        "testl %eax, (%ecx)\n\t"
+        "subl $0x1000, %eax\n\t"
+        "cmpl $0x1000, %eax\n\t"
+        "ja 2b\n\t"
+        "1:\n\t"
+        "subl %eax, %ecx\n\t"
+        "testl %eax, (%ecx)\n\t"
+        "popl %eax\n\t"
+        "popl %ecx\n\t"
+        "ret\n\t"
+    );
+}
+
+extern "C" void __cxa_pure_virtual(void) {
+    ExitProcess(1);
+}
+
+extern "C" void __main(void) {
+    xpmgr_ctor* ctor;
+    if (!__init_array_start || !__init_array_end) {
+        return;
+    }
+    for (ctor = __init_array_start; ctor < __init_array_end; ctor++) {
+        if (*ctor) {
+            (*ctor)();
+        }
+    }
+}
+
+static int is_space(char ch) {
+    return ch == ' ' || ch == '\t' || ch == '\r' || ch == '\n';
+}
+
+extern "C" void mainCRTStartup(void) {
+    char* command = GetCommandLineA();
+    char* buffer;
+    char** argv;
+    int length = 0;
+    int argc = 0;
+    char* cursor;
+    HANDLE heap = GetProcessHeap();
+
+    if (!command) {
+        command = (char*)"";
+    }
+    while (command[length]) {
+        length++;
+    }
+
+    buffer = (char*)HeapAlloc(heap, 0, (SIZE_T)length + 1);
+    argv = (char**)HeapAlloc(heap, HEAP_ZERO_MEMORY, (SIZE_T)(length + 2) * sizeof(char*));
+    if (!buffer || !argv) {
+        ExitProcess(1);
+    }
+    for (int index = 0; index <= length; index++) {
+        buffer[index] = command[index];
+    }
+
+    cursor = buffer;
+    while (*cursor) {
+        char* out;
+        int quoted = 0;
+        int more;
+        while (is_space(*cursor)) {
+            cursor++;
+        }
+        if (!*cursor) {
+            break;
+        }
+        argv[argc++] = cursor;
+        out = cursor;
+        while (*cursor) {
+            if (*cursor == '"') {
+                quoted = !quoted;
+                cursor++;
+                continue;
+            }
+            if (!quoted && is_space(*cursor)) {
+                break;
+            }
+            *out++ = *cursor++;
+        }
+        more = *cursor != 0;
+        *out = 0;
+        if (more) {
+            cursor++;
+        }
+    }
+    argv[argc] = NULL;
+
+    ExitProcess((UINT)main(argc, argv));
+}