kernel: use mpaland printf

.gitignore

@@ -9,3 +9,5 @@ pkgs
 sources
 astral.iso
 kernel-src/include/limine.h
+kernel-src/include/printf.h
+kernel-src/io/printf.c

Makefile

@@ -27,7 +27,7 @@ kernel:
 	./jinx build astral
 
 clean-kernel:
-	find kernel-src -name *.o -delete
+	find builds/astral/ -name *.o -delete
 
 clean:
 	make clean-kernel

kernel-src/Makefile

@@ -5,7 +5,9 @@ TARGET=x86-64
 INCDIR=$(shell pwd)/include
 ARCHDIR=$(shell pwd)/arch/$(TARGET)/
 LDFLAGS=-ffreestanding -nostdlib -lgcc -Wl,-T,"$(ARCHDIR)/kernel.ld" -debug
-CFLAGS=-ffreestanding -mcmodel=kernel -O2 -mno-red-zone -mno-mmx -mno-sse -mno-sse2 -nostdlib -I "${INCDIR}"
+# required for mpaland printf so it doesn't compile with floating point support, which results in build failures
+PRINTFOPTS=-DPRINTF_DISABLE_SUPPORT_FLOAT
+CFLAGS=-ffreestanding -mcmodel=kernel -O2 -mno-red-zone -mno-mmx -mno-sse -mno-sse2 -nostdlib -Wall -I "${INCDIR}" $(PRINTFOPTS)
 ASFLAGS=-felf64
 
 astral:	$(OBJS)

kernel-src/arch/x86-64/e9.c

@@ -1,5 +1,3 @@
-
-
 #include <arch/io.h>
 
 // TODO compile time options for disabling output to port e9h

kernel-src/arch/x86-64/main.c

@@ -1,7 +1,7 @@
 #include <arch/e9.h>
+#include <logging.h>
 
 void kernel_entry() {
-	arch_e9_puts("Hello, world!\n");
-	asm("cli");
-	asm("hlt");
+	logging_sethook(arch_e9_putc);
+	__assert(!"kernel entry end");
 }

kernel-src/include/logging.h

@@ -0,0 +1,18 @@
+#ifndef _LOGGING_H
+#define _LOGGING_H
+
+#include <printf.h>
+
+void _putchar(char c);
+void logging_sethook(void (*fun)(char));
+
+// TODO panic
+
+#define __assert(x) \
+	if (!(x)){ \
+		printf("%s:%s:%d: %s failed\n", __FILE__, __func__, __LINE__, #x); \
+		for(;;); \
+	};
+
+
+#endif

kernel-src/io/logging.c

@@ -0,0 +1,14 @@
+static void nohook(char c) {
+
+}
+
+static void (*hook)(char) = nohook;
+
+// hook used by mpaland printf
+void _putchar(char c) {
+	hook(c);
+}
+
+void logging_sethook(void (*fun)(char)) {
+	hook = fun;
+}

source-recipes/astral

@@ -2,7 +2,14 @@ name=astral
 version=0
 source_dir="kernel-src"
 allow_network="yes"
+imagedeps="wget"
 
 regenerate() {
 	curl https://raw.githubusercontent.com/limine-bootloader/limine/trunk/limine.h > include/limine.h
+	pushd /tmp/
+	wget https://github.com/mpaland/printf/archive/refs/tags/v4.0.0.tar.gz
+	tar -xf v4.0.0.tar.gz
+	popd
+	cp /tmp/printf-4.0.0/printf.c io/printf.c
+	cp /tmp/printf-4.0.0/printf.h include/printf.h
 }