Add qemu 2.4.0
[kvmfornfv.git] / qemu / tests / tcg / runcom.c
diff --git a/qemu/tests/tcg/runcom.c b/qemu/tests/tcg/runcom.c
new file mode 100644 (file)
index 0000000..d60342b
--- /dev/null
@@ -0,0 +1,192 @@
+/*
+ * Simple example of use of vm86: launch a basic .com DOS executable
+ */
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <inttypes.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <sys/mman.h>
+#include <signal.h>
+
+#include <linux/unistd.h>
+#include <asm/vm86.h>
+
+extern int vm86 (unsigned long int subfunction,
+                struct vm86plus_struct *info);
+
+#define VIF_MASK                0x00080000
+
+//#define SIGTEST
+
+#define COM_BASE_ADDR    0x10100
+
+static void usage(void)
+{
+    printf("runcom version 0.1 (c) 2003 Fabrice Bellard\n"
+           "usage: runcom file.com\n"
+           "VM86 Run simple .com DOS executables (linux vm86 test mode)\n");
+    exit(1);
+}
+
+static inline void set_bit(uint8_t *a, unsigned int bit)
+{
+    a[bit / 8] |= (1 << (bit % 8));
+}
+
+static inline uint8_t *seg_to_linear(unsigned int seg, unsigned int reg)
+{
+    return (uint8_t *)((seg << 4) + (reg & 0xffff));
+}
+
+static inline void pushw(struct vm86_regs *r, int val)
+{
+    r->esp = (r->esp & ~0xffff) | ((r->esp - 2) & 0xffff);
+    *(uint16_t *)seg_to_linear(r->ss, r->esp) = val;
+}
+
+void dump_regs(struct vm86_regs *r)
+{
+    fprintf(stderr,
+            "EAX=%08lx EBX=%08lx ECX=%08lx EDX=%08lx\n"
+            "ESI=%08lx EDI=%08lx EBP=%08lx ESP=%08lx\n"
+            "EIP=%08lx EFL=%08lx\n"
+            "CS=%04x DS=%04x ES=%04x SS=%04x FS=%04x GS=%04x\n",
+            r->eax, r->ebx, r->ecx, r->edx, r->esi, r->edi, r->ebp, r->esp,
+            r->eip, r->eflags,
+            r->cs, r->ds, r->es, r->ss, r->fs, r->gs);
+}
+
+#ifdef SIGTEST
+void alarm_handler(int sig)
+{
+    fprintf(stderr, "alarm signal=%d\n", sig);
+    alarm(1);
+}
+#endif
+
+int main(int argc, char **argv)
+{
+    uint8_t *vm86_mem;
+    const char *filename;
+    int fd, ret, seg;
+    struct vm86plus_struct ctx;
+    struct vm86_regs *r;
+
+    if (argc != 2)
+        usage();
+    filename = argv[1];
+
+    vm86_mem = mmap((void *)0x00000000, 0x110000,
+                    PROT_WRITE | PROT_READ | PROT_EXEC,
+                    MAP_FIXED | MAP_ANON | MAP_PRIVATE, -1, 0);
+    if (vm86_mem == MAP_FAILED) {
+        perror("mmap");
+        exit(1);
+    }
+#ifdef SIGTEST
+    {
+        struct sigaction act;
+
+        act.sa_handler = alarm_handler;
+        sigemptyset(&act.sa_mask);
+        act.sa_flags = 0;
+        sigaction(SIGALRM, &act, NULL);
+        alarm(1);
+    }
+#endif
+
+    /* load the MSDOS .com executable */
+    fd = open(filename, O_RDONLY);
+    if (fd < 0) {
+        perror(filename);
+        exit(1);
+    }
+    ret = read(fd, vm86_mem + COM_BASE_ADDR, 65536 - 256);
+    if (ret < 0) {
+        perror("read");
+        exit(1);
+    }
+    close(fd);
+
+    memset(&ctx, 0, sizeof(ctx));
+    /* init basic registers */
+    r = &ctx.regs;
+    r->eip = 0x100;
+    r->esp = 0xfffe;
+    seg = (COM_BASE_ADDR - 0x100) >> 4;
+    r->cs = seg;
+    r->ss = seg;
+    r->ds = seg;
+    r->es = seg;
+    r->fs = seg;
+    r->gs = seg;
+    r->eflags = VIF_MASK;
+
+    /* put return code */
+    set_bit((uint8_t *)&ctx.int_revectored, 0x21);
+    *seg_to_linear(r->cs, 0) = 0xb4; /* mov ah, $0 */
+    *seg_to_linear(r->cs, 1) = 0x00;
+    *seg_to_linear(r->cs, 2) = 0xcd; /* int $0x21 */
+    *seg_to_linear(r->cs, 3) = 0x21;
+    pushw(&ctx.regs, 0x0000);
+
+    /* the value of these registers seem to be assumed by pi_10.com */
+    r->esi = 0x100;
+    r->ecx = 0xff;
+    r->ebp = 0x0900;
+    r->edi = 0xfffe;
+
+    for(;;) {
+        ret = vm86(VM86_ENTER, &ctx);
+        switch(VM86_TYPE(ret)) {
+        case VM86_INTx:
+            {
+                int int_num, ah;
+
+                int_num = VM86_ARG(ret);
+                if (int_num != 0x21)
+                    goto unknown_int;
+                ah = (r->eax >> 8) & 0xff;
+                switch(ah) {
+                case 0x00: /* exit */
+                    exit(0);
+                case 0x02: /* write char */
+                    {
+                        uint8_t c = r->edx;
+                        write(1, &c, 1);
+                    }
+                    break;
+                case 0x09: /* write string */
+                    {
+                        uint8_t c;
+                        for(;;) {
+                            c = *seg_to_linear(r->ds, r->edx);
+                            if (c == '$')
+                                break;
+                            write(1, &c, 1);
+                        }
+                        r->eax = (r->eax & ~0xff) | '$';
+                    }
+                    break;
+                default:
+                unknown_int:
+                    fprintf(stderr, "unsupported int 0x%02x\n", int_num);
+                    dump_regs(&ctx.regs);
+                    //                    exit(1);
+                }
+            }
+            break;
+        case VM86_SIGNAL:
+            /* a signal came, we just ignore that */
+            break;
+        case VM86_STI:
+            break;
+        default:
+            fprintf(stderr, "unhandled vm86 return code (0x%x)\n", ret);
+            dump_regs(&ctx.regs);
+            exit(1);
+        }
+    }
+}