sample/filetest.c

   1 #include <com32.h>
   2 #include <stdarg.h>
   3
   4 #define NULL ((void *)0)
   5 int printf(const char *, ...);
   6 int putchar(int);
   7
   8 static inline void memset(void *buf, int ch, unsigned int len)
   9 {
  10     asm volatile ("cld; rep; stosb":"+D" (buf), "+c"(len):"a"(ch):"memory");
  11 }
  12
  13 static void strcpy(char *dst, const char *src)
  14 {
  15     while (*src)
  16         *dst++ = *src++;
  17
  18     *dst = '\0';
  19 }
  20
  21 static void printregs(const com32sys_t * r)
  22 {
  23     printf("eflags = %08x  ds = %04x  es = %04x  fs = %04x  gs = %04x\n"
  24            "eax = %08x  ebx = %08x  ecx = %08x  edx = %08x\n"
  25            "ebp = %08x  esi = %08x  edi = %08x  esp = %08x\n",
  26            r->eflags.l, r->ds, r->es, r->fs, r->gs,
  27            r->eax.l, r->ebx.l, r->ecx.l, r->edx.l,
  28            r->ebp.l, r->esi.l, r->edi.l, r->_unused_esp.l);
  29 }
  30
  31 int __start(void)
  32 {
  33     unsigned int ax, cx, si, t;
  34     com32sys_t inreg, outreg;
  35     char *p;
  36
  37     /* Test null system call */
  38     inreg.eflags.l = 0xffffffff;
  39     inreg.eax.l = 0x11110000;
  40     inreg.ecx.l = 0x22222222;
  41     inreg.edx.l = 0x33333333;
  42     inreg.ebx.l = 0x44444444;
  43     inreg.ebp.l = 0x55555555;
  44     inreg.esi.l = 0x66666666;
  45     inreg.edi.l = 0x77777777;
  46     inreg.ds = 0xaaaa;
  47     inreg.es = 0xbbbb;
  48     inreg.fs = 0xcccc;
  49     inreg.gs = 0xdddd;
  50     printregs(&inreg);
  51     __com32.cs_intcall(0x22, &inreg, &outreg);
  52     printregs(&outreg);
  53     printf("----\n");
  54
  55     memset(&inreg, 0, sizeof inreg);
  56     memset(&outreg, 0, sizeof outreg);
  57     strcpy(__com32.cs_bounce, "test.txt");
  58     inreg.eax.w[0] = 0x0006;    // Open file
  59     inreg.esi.w[0] = OFFS(__com32.cs_bounce);
  60     inreg.es = SEG(__com32.cs_bounce);
  61     printregs(&inreg);
  62     __com32.cs_intcall(0x22, &inreg, &outreg);
  63     printregs(&outreg);
  64     printf("----\n");
  65
  66     si = outreg.esi.w[0];       /* File handle */
  67     cx = outreg.ecx.w[0];       /* Block size */
  68     ax = outreg.eax.l;          /* File length */
  69
  70     while (si) {
  71         /* We can only read 64K per call */
  72         t = (ax > 65536) ? 65536 / cx : (ax + cx - 1) / cx;
  73
  74         memset(&inreg, 0, sizeof inreg);
  75         inreg.esi.w[0] = si;
  76         inreg.ecx.w[0] = t;     /* Block count */
  77         inreg.eax.w[0] = 0x0007;        // Read file
  78         inreg.ebx.w[0] = OFFS(__com32.cs_bounce);
  79         inreg.es = SEG(__com32.cs_bounce);
  80         printregs(&inreg);
  81         __com32.cs_intcall(0x22, &inreg, &outreg);
  82         printregs(&outreg);
  83         printf("----\n");
  84         si = outreg.esi.w[0];
  85
  86         /* Print the buffer */
  87         t = (ax < 65536) ? ax : 65536;
  88         p = __com32.cs_bounce;
  89         while (t) {
  90             putchar(*p++);
  91             t--;
  92             ax--;
  93         }
  94     }
  95
  96     return 0;
  97 }