[lib][libc] move all the printf routines into printf.c

Some of the wrapper routines (printf, fprintf, etc) were defined in
stdio.c which is not necessarily compiled with the same compiler flags
concerning floating point support.

On some architectures (arm64, x86-64) this caused the wrapper routines
to clobber the floating point registers prior to getting into the
printf_engine.

lib/libc/printf.c

@@ -6,7 +6,6 @@
  * https://opensource.org/licenses/MIT
  */
 #include <lk/debug.h>
-#include <assert.h>
 #include <limits.h>
 #include <printf.h>
 #include <stdarg.h>
@@ -15,6 +14,10 @@
 #include <string.h>
 #include <platform/debug.h>
 
+// The main printf engine and all of the printf wrapper routines.
+// It's important these are all in the same file, or at least all
+// compiled with the same flags concerning floating point support.
+
 #if WITH_NO_FP
 #define FLOAT_PRINTF 0
 #else
@@ -90,6 +93,37 @@ int vsnprintf(char *str, size_t len, const char *fmt, va_list ap) {
     return wlen;
 }
 
+int vfprintf(FILE *fp, const char *fmt, va_list ap) {
+    return _printf_engine(&_fprintf_output_func, (void *)fp, fmt, ap);
+}
+
+int fprintf(FILE *fp, const char *fmt, ...) {
+    va_list ap;
+    int err;
+
+    va_start(ap, fmt);
+    err = vfprintf(fp, fmt, ap);
+    va_end(ap);
+    return err;
+}
+
+#if !DISABLE_DEBUG_OUTPUT
+int printf(const char *fmt, ...) {
+    va_list ap;
+    int err;
+
+    va_start(ap, fmt);
+    err = vfprintf(stdout, fmt, ap);
+    va_end(ap);
+
+    return err;
+}
+
+int vprintf(const char *fmt, va_list ap) {
+    return vfprintf(stdout, fmt, ap);
+}
+#endif // !DISABLE_DEBUG_OUTPUT
+
 #define LONGFLAG       0x00000001
 #define LONGLONGFLAG   0x00000002
 #define HALFFLAG       0x00000004

lib/libc/rules.mk

@@ -12,13 +12,13 @@ MODULE_SRCS += \
 	$(LOCAL_DIR)/atoi.c \
 	$(LOCAL_DIR)/bsearch.c \
 	$(LOCAL_DIR)/ctype.c \
+	$(LOCAL_DIR)/eabi.c \
 	$(LOCAL_DIR)/errno.c \
+	$(LOCAL_DIR)/qsort.c \
 	$(LOCAL_DIR)/rand.c \
+	$(LOCAL_DIR)/stdio.c \
 	$(LOCAL_DIR)/strtol.c \
 	$(LOCAL_DIR)/strtoll.c \
-	$(LOCAL_DIR)/stdio.c \
-	$(LOCAL_DIR)/qsort.c \
-	$(LOCAL_DIR)/eabi.c
 
 MODULE_FLOAT_SRCS += \
 	$(LOCAL_DIR)/printf.c \

lib/libc/stdio.c

@@ -287,34 +287,3 @@ int _fprintf_output_func(const char *str, size_t len, void *state) {
 
     return fwrite_error(str, /*size=*/1, /*count=*/len, fp);
 }
-
-int vfprintf(FILE *fp, const char *fmt, va_list ap) {
-    return _printf_engine(&_fprintf_output_func, (void *)fp, fmt, ap);
-}
-
-int fprintf(FILE *fp, const char *fmt, ...) {
-    va_list ap;
-    int err;
-
-    va_start(ap, fmt);
-    err = vfprintf(fp, fmt, ap);
-    va_end(ap);
-    return err;
-}
-
-#if !DISABLE_DEBUG_OUTPUT
-int printf(const char *fmt, ...) {
-    va_list ap;
-    int err;
-
-    va_start(ap, fmt);
-    err = vfprintf(stdout, fmt, ap);
-    va_end(ap);
-
-    return err;
-}
-
-int vprintf(const char *fmt, va_list ap) {
-    return vfprintf(stdout, fmt, ap);
-}
-#endif // !DISABLE_DEBUG_OUTPUT