[metal] Add a uprintf() routine, for non-emergency boot logging

libc/integral/c.inc

@@ -735,6 +735,8 @@ void abort(void) wontreturn;
 #endif
 
 #define __weak_reference(sym, alias)       \
+  __weak_reference_impl(sym, alias)
+#define __weak_reference_impl(sym, alias)  \
   __asm__(".weak\t" #alias "\n\t"          \
           ".equ\t" #alias ", " #sym "\n\t" \
           ".type\t" #alias ",@notype")

libc/intrin/interrupts.S

@@ -26,6 +26,7 @@
 ╚─────────────────────────────────────────────────────────────────────────────*/
 #include "libc/dce.h"
 #include "libc/macros.internal.h"
+#include "libc/intrin/kprintf.h"
 #include "libc/runtime/pc.internal.h"
 
 //	Code and data structures for bare metal interrupt handling.

libc/intrin/kprintf.greg.c

@@ -385,14 +385,29 @@ privileged long kloghandle(void) {
   return __klog_handle;
 }
 
+privileged void _klog_serial(const char *b, size_t n) {
+  size_t i;
+  uint16_t dx;
+  unsigned char al;
+  for (i = 0; i < n; ++i) {
+    for (;;) {
+      dx = 0x3F8 + UART_LSR;
+      asm("inb\t%1,%0" : "=a"(al) : "dN"(dx));
+      if (al & UART_TTYTXR) break;
+      asm("pause");
+    }
+    dx = 0x3F8;
+    asm volatile("outb\t%0,%1"
+                 : /* no inputs */
+                 : "a"(b[i]), "dN"(dx));
+  }
+}
+
 privileged void klog(const char *b, size_t n) {
 #ifdef __x86_64__
   int e;
   long h;
-  size_t i;
-  uint16_t dx;
   uint32_t wrote;
-  unsigned char al;
   long rax, rdi, rsi, rdx;
   if ((h = kloghandle()) == -1) {
     return;
@@ -407,18 +422,7 @@ privileged void klog(const char *b, size_t n) {
     if (_weaken(_klog_vga)) {
       _weaken(_klog_vga)(b, n);
     }
-    for (i = 0; i < n; ++i) {
-      for (;;) {
-        dx = 0x3F8 + UART_LSR;
-        asm("inb\t%1,%0" : "=a"(al) : "dN"(dx));
-        if (al & UART_TTYTXR) break;
-        asm("pause");
-      }
-      dx = 0x3F8;
-      asm volatile("outb\t%0,%1"
-                   : /* no inputs */
-                   : "a"(b[i]), "dN"(dx));
-    }
+    _klog_serial(b, n);
   } else {
     asm volatile("syscall"
                  : "=a"(rax), "=D"(rdi), "=S"(rsi), "=d"(rdx)
@@ -1152,3 +1156,6 @@ privileged void kprintf(const char *fmt, ...) {
   kvprintf(fmt, v);
   va_end(v);
 }
+
+__weak_reference(kprintf, uprintf);
+__weak_reference(kvprintf, uvprintf);

libc/intrin/kprintf.h

@@ -9,25 +9,49 @@
 #define kvsnprintf   __kvsnprintf
 #define kloghandle   __kloghandle
 #define kisdangerous __kisdangerous
+#define uprintf      __uprintf
+#define uvprintf     __uvprintf
 
 #if !(__ASSEMBLER__ + __LINKER__ + 0)
+
 COSMOPOLITAN_C_START_
 
-void kprintf(const char *, ...);
-size_t ksnprintf(char *, size_t, const char *, ...);
-void kvprintf(const char *, va_list);
-size_t kvsnprintf(char *, size_t, const char *, va_list);
-bool kisdangerous(const void *);
-
 void kprintf(const char *, ...);
 size_t ksnprintf(char *, size_t, const char *, ...);
 void kvprintf(const char *, va_list);
 size_t kvsnprintf(char *, size_t, const char *, va_list);
 
 bool kisdangerous(const void *);
+
 void klog(const char *, size_t);
+void _klog_serial(const char *, size_t);
 long kloghandle(void);
 
+void uprintf(const char *, ...);
+void uvprintf(const char *, va_list);
+
+#ifndef TINY
+#define KINFOF(FMT, ...)                                      \
+        do {                                                  \
+          uprintf("\r\e[35m%s:%d: " FMT "\e[0m\n",            \
+                  __FILE__, __LINE__, ## __VA_ARGS__);        \
+        } while (0)
+#define KWARNF(FMT, ...)                                      \
+        do {                                                  \
+          uprintf("\r\e[94;49mwarn: %s:%d: " FMT "\e[0m\n",   \
+                  __FILE__, __LINE__, ## __VA_ARGS__);        \
+        } while (0)
+#else
+#define KINFOF(FMT, ...) ((void)0)
+#define KWARNF(FMT, ...) ((void)0)
+#endif
+#define KDIEF(FMT, ...)                                       \
+        do {                                                  \
+          kprintf("\r\e[30;101mfatal: %s:%d: " FMT "\e[0m\n", \
+                  __FILE__, __LINE__, ## __VA_ARGS__);        \
+          for (;;) asm volatile("cli\n\thlt");                \
+        } while (0)
+
 COSMOPOLITAN_C_END_
 #endif /* !(__ASSEMBLER__ + __LINKER__ + 0) */
 #endif /* _COSMO_SOURCE */

libc/vga/tty-klog.greg.c

@@ -33,8 +33,8 @@
 #ifdef __x86_64__
 
 /*
- * @fileoverview Instantiation of routines for emergency or system console
- * output in graphical video modes.
+ * @fileoverview Instantiation of routines for emergency console output in
+ * graphical video modes.
  *
  * @see libc/vga/tty-graph.inc
  */

libc/vga/vga-init.greg.c

@@ -25,7 +25,10 @@
 │ OTHER DEALINGS IN THE SOFTWARE.                                              │
 ╚─────────────────────────────────────────────────────────────────────────────*/
 #include "libc/dce.h"
+#include "libc/intrin/kprintf.h"
 #include "libc/runtime/pc.internal.h"
+#include "libc/runtime/runtime.h"
+#include "libc/runtime/stack.h"
 #include "libc/str/str.h"
 #include "libc/vga/vga.internal.h"
 
@@ -72,4 +75,47 @@ textstartup void _vga_init(void) {
   }
 }
 
+#if !IsTiny()
+/**
+ * Non-emergency console vprintf(), useful for dumping debugging or
+ * informational messages at program startup.
+ *
+ * @see uprintf()
+ */
+void uvprintf(const char *fmt, va_list v) {
+  if (!IsMetal()) {
+    kvprintf(fmt, v);
+  } else {
+    long size = __get_safe_size(8000, 3000);
+    char *buf = alloca(size);
+    CheckLargeStackAllocation(buf, size);
+    size_t count = kvsnprintf(buf, size, fmt, v);
+    if (count >= size) count = size - 1;
+    _TtyWrite(&_vga_tty, buf, count);
+    _klog_serial(buf, count);
+  }
+}
+
+/**
+ * Non-emergency console printf(), useful for dumping debugging or
+ * informational messages at program startup.
+ *
+ * uprintf() is similar to kprintf(), but on bare metal with VGA support, it
+ * uses the normal, fast graphical console, rather than initializing an
+ * emergency console.  This makes uprintf() faster — on bare metal — at the
+ * expense of being less crash-proof.
+ *
+ * (The uprintf() function name comes from the FreeBSD kernel.)
+ *
+ * @see kprintf()
+ * @see https://man.freebsd.org/cgi/man.cgi?query=uprintf&sektion=9&n=1
+ */
+void uprintf(const char *fmt, ...) {
+  va_list v;
+  va_start(v, fmt);
+  uvprintf(fmt, v);
+  va_end(v);
+}
+#endif /* !IsTiny() */
+
 #endif /* __x86_64__ */

libc/vga/vga.internal.h

@@ -255,8 +255,7 @@ void _TtyGraphMoveLineCells(struct Tty *, size_t, size_t, size_t, size_t,
                             size_t);
 
 /*
- * Routines that implement emergency or system console output in graphical
- * video modes.
+ * Routines that implement emergency console output in graphical video modes.
  */
 void _TtyKlog16Update(struct Tty *);
 void _TtyKlog16DrawChar(struct Tty *, size_t, size_t, wchar_t);