// Misc utility functions.
//
-// Copyright (C) 2008 Kevin O'Connor <kevin@koconnor.net>
+// Copyright (C) 2008,2009 Kevin O'Connor <kevin@koconnor.net>
//
// This file may be distributed under the terms of the GNU LGPLv3 license.
#include "util.h" // call16
#include "bregs.h" // struct bregs
-#include "farptr.h" // GET_FLATPTR
-#include "biosvar.h" // get_ebda_seg
+#include "config.h" // BUILD_STACK_ADDR
+
+
+/****************************************************************
+ * 16bit calls
+ ****************************************************************/
// Call a function with a specified register state. Note that on
// return, the interrupt enable/disable flag may be altered.
inline void
call16(struct bregs *callregs)
{
+ if (!MODESEGMENT && getesp() > BUILD_STACK_ADDR)
+ panic("call16 with invalid stack\n");
asm volatile(
#if MODE16 == 1
"calll __call16\n"
+ "cli\n"
+ "cld"
#else
- "calll __call16_from32\n"
+ "calll __call16_from32"
#endif
: "+a" (callregs), "+m" (*callregs)
:
- : "ebx", "ecx", "edx", "esi", "edi", "ebp", "cc", "memory");
+ : "ebx", "ecx", "edx", "esi", "edi", "cc", "memory");
}
inline void
call16big(struct bregs *callregs)
{
- extern void __force_link_error__call16big_only_in_32bit_mode();
- if (MODE16)
- __force_link_error__call16big_only_in_32bit_mode();
-
+ ASSERT32FLAT();
+ if (getesp() > BUILD_STACK_ADDR)
+ panic("call16 with invalid stack\n");
asm volatile(
- "calll __call16big_from32\n"
+ "calll __call16big_from32"
: "+a" (callregs), "+m" (*callregs)
:
- : "ebx", "ecx", "edx", "esi", "edi", "ebp", "cc", "memory");
+ : "ebx", "ecx", "edx", "esi", "edi", "cc", "memory");
}
inline void
__call16_int(struct bregs *callregs, u16 offset)
{
- if (MODE16)
- callregs->cs = GET_SEG(CS);
+ if (MODESEGMENT)
+ callregs->code.seg = GET_SEG(CS);
else
- callregs->cs = SEG_BIOS;
- callregs->ip = offset;
+ callregs->code.seg = SEG_BIOS;
+ callregs->code.offset = offset;
call16(callregs);
}
-inline void
-call16_simpint(int nr, u32 *eax, u32 *flags)
-{
- extern void __force_link_error__call16_simpint_only_in_16bit_mode();
- if (!MODE16)
- __force_link_error__call16_simpint_only_in_16bit_mode();
- asm volatile(
- "stc\n"
- "int %2\n"
- "pushfl\n"
- "popl %1\n"
- "cld\n"
- "cli\n"
- : "+a"(*eax), "=r"(*flags)
- : "i"(nr)
- : "cc", "memory");
-}
-
-// Switch to the extra stack in ebda and call a function.
-inline u32
-stack_hop(u32 eax, u32 edx, u32 ecx, void *func)
-{
- extern void __force_link_error__stack_hop_only_in_16bit_mode();
- if (!MODE16)
- __force_link_error__stack_hop_only_in_16bit_mode();
-
- u16 ebda_seg = get_ebda_seg(), bkup_ss;
- u32 bkup_esp;
- asm volatile(
- // Backup current %ss/%esp values.
- "movw %%ss, %w3\n"
- "movl %%esp, %4\n"
- // Copy ebda seg to %ds/%ss and set %esp
- "movw %w6, %%ds\n"
- "movw %w6, %%ss\n"
- "movl %5, %%esp\n"
- // Call func
- "calll %7\n"
- // Restore segments and stack
- "movw %w3, %%ds\n"
- "movw %w3, %%ss\n"
- "movl %4, %%esp\n"
- : "+a" (eax), "+d" (edx), "+c" (ecx), "=&r" (bkup_ss), "=&r" (bkup_esp)
- : "i" (EBDA_OFFSET_TOP_STACK), "r" (ebda_seg), "m" (*(u8*)func)
- : "cc", "memory");
- return eax;
-}
+/****************************************************************
+ * String ops
+ ****************************************************************/
// Sum the bytes in the specified area.
u8
-checksum_far(u16 buf_seg, u8 *buf_far, u32 len)
+checksum_far(u16 buf_seg, void *buf_far, u32 len)
{
SET_SEG(ES, buf_seg);
u32 i;
u8 sum = 0;
for (i=0; i<len; i++)
- sum += GET_VAR(ES, buf_far[i]);
+ sum += GET_VAR(ES, ((u8*)buf_far)[i]);
return sum;
}
u8
-checksum(u8 *buf, u32 len)
+checksum(void *buf, u32 len)
{
return checksum_far(GET_SEG(SS), buf, len);
}
+size_t
+strlen(const char *s)
+{
+ if (__builtin_constant_p(s))
+ return __builtin_strlen(s);
+ const char *p = s;
+ while (*p)
+ p++;
+ return p-s;
+}
+
+// Compare two areas of memory.
+int
+memcmp(const void *s1, const void *s2, size_t n)
+{
+ while (n) {
+ if (*(u8*)s1 != *(u8*)s2)
+ return *(u8*)s1 < *(u8*)s2 ? -1 : 1;
+ s1++;
+ s2++;
+ n--;
+ }
+ return 0;
+}
+
+// Compare two strings.
+int
+strcmp(const char *s1, const char *s2)
+{
+ for (;;) {
+ if (*s1 != *s2)
+ return *s1 < *s2 ? -1 : 1;
+ if (! *s1)
+ return 0;
+ s1++;
+ s2++;
+ }
+}
+
+inline void
+memset_far(u16 d_seg, void *d_far, u8 c, size_t len)
+{
+ SET_SEG(ES, d_seg);
+ asm volatile(
+ "rep stosb %%es:(%%di)"
+ : "+c"(len), "+D"(d_far)
+ : "a"(c)
+ : "cc", "memory");
+}
+
+inline void
+memset16_far(u16 d_seg, void *d_far, u16 c, size_t len)
+{
+ len /= 2;
+ SET_SEG(ES, d_seg);
+ asm volatile(
+ "rep stosw %%es:(%%di)"
+ : "+c"(len), "+D"(d_far)
+ : "a"(c)
+ : "cc", "memory");
+}
+
void *
memset(void *s, int c, size_t n)
{
return s;
}
+void memset_fl(void *ptr, u8 val, size_t size)
+{
+ if (MODESEGMENT)
+ memset_far(FLATPTR_TO_SEG(ptr), (void*)(FLATPTR_TO_OFFSET(ptr)),
+ val, size);
+ else
+ memset(ptr, val, size);
+}
+
inline void
memcpy_far(u16 d_seg, void *d_far, u16 s_seg, const void *s_far, size_t len)
{
"movw %%ds, %w0\n"
"movw %w4, %%ds\n"
"rep movsb (%%si),%%es:(%%di)\n"
- "movw %w0, %%ds\n"
+ "movw %w0, %%ds"
: "=&r"(bkup_ds), "+c"(len), "+S"(s_far), "+D"(d_far)
: "r"(s_seg)
: "cc", "memory");
}
+inline void
+memcpy_fl(void *d_fl, const void *s_fl, size_t len)
+{
+ if (MODESEGMENT)
+ memcpy_far(FLATPTR_TO_SEG(d_fl), (void*)FLATPTR_TO_OFFSET(d_fl)
+ , FLATPTR_TO_SEG(s_fl), (void*)FLATPTR_TO_OFFSET(s_fl)
+ , len);
+ else
+ memcpy(d_fl, s_fl, len);
+}
+
void *
+#undef memcpy
memcpy(void *d1, const void *s1, size_t len)
+#if MODESEGMENT == 0
+#define memcpy __builtin_memcpy
+#endif
{
- u8 *d = (u8*)d1, *s = (u8*)s1;
- while (len--)
- *d++ = *s++;
+ SET_SEG(ES, GET_SEG(SS));
+ void *d = d1;
+ if (((u32)d1 | (u32)s1 | len) & 3) {
+ // non-aligned memcpy
+ asm volatile(
+ "rep movsb (%%esi),%%es:(%%edi)"
+ : "+c"(len), "+S"(s1), "+D"(d)
+ : : "cc", "memory");
+ return d1;
+ }
+ // Common case - use 4-byte copy
+ len /= 4;
+ asm volatile(
+ "rep movsl (%%esi),%%es:(%%edi)"
+ : "+c"(len), "+S"(s1), "+D"(d)
+ : : "cc", "memory");
return d1;
}
+// Copy to/from memory mapped IO. IO mem is very slow, so yield
+// periodically.
+void
+iomemcpy(void *d, const void *s, u32 len)
+{
+ yield();
+ while (len > 3) {
+ u32 copylen = len;
+ if (copylen > 2048)
+ copylen = 2048;
+ copylen /= 4;
+ len -= copylen * 4;
+ asm volatile(
+ "rep movsl (%%esi),%%es:(%%edi)"
+ : "+c"(copylen), "+S"(s), "+D"(d)
+ : : "cc", "memory");
+ yield();
+ }
+ if (len)
+ // Copy any remaining bytes.
+ memcpy(d, s, len);
+}
+
void *
memmove(void *d, const void *s, size_t len)
{
strtcpy(char *dest, const char *src, size_t len)
{
char *d = dest;
- while (len-- && *src != '\0')
+ while (--len && *src != '\0')
*d++ = *src++;
*d = '\0';
return dest;
}
-// Wait for 'usec' microseconds with irqs enabled.
+// locate first occurance of character c in the string s
+char *
+strchr(const char *s, int c)
+{
+ for (; *s; s++)
+ if (*s == c)
+ return (char*)s;
+ return NULL;
+}
+
+// Remove any trailing blank characters (spaces, new lines, carriage returns)
void
-usleep(u32 usec)
+nullTrailingSpace(char *buf)
{
- struct bregs br;
- memset(&br, 0, sizeof(br));
- br.ah = 0x86;
- br.cx = usec >> 16;
- br.dx = usec;
- call16_int(0x15, &br);
+ int len = strlen(buf);
+ char *end = &buf[len-1];
+ while (end >= buf && *end <= ' ')
+ *(end--) = '\0';
}
+/****************************************************************
+ * Keyboard calls
+ ****************************************************************/
+
// See if a keystroke is pending in the keyboard buffer.
static int
-check_for_keystroke()
+check_for_keystroke(void)
{
struct bregs br;
memset(&br, 0, sizeof(br));
+ br.flags = F_IF;
br.ah = 1;
call16_int(0x16, &br);
return !(br.flags & F_ZF);
// Return a keystroke - waiting forever if necessary.
static int
-get_raw_keystroke()
+get_raw_keystroke(void)
{
struct bregs br;
memset(&br, 0, sizeof(br));
+ br.flags = F_IF;
call16_int(0x16, &br);
return br.ah;
}
int
get_keystroke(int msec)
{
+ u32 end = calc_future_timer(msec);
for (;;) {
if (check_for_keystroke())
return get_raw_keystroke();
- if (msec <= 0)
+ if (check_timer(end))
return -1;
- usleep(50*1000);
- msec -= 50;
+ wait_irq();
}
}