Build folder + coding style guidelines

Reviewed-on: xamidev/pepperOS#12

.gitignore

@@ -11,3 +11,4 @@ iso_root
 symbols.map
 symbols.S
 *.log
+build/

DOOM.txt

@@ -1,24 +0,0 @@
-up to doom:
-
-- Return from pedicel_main() normally (to idle)
-
-** Checkpoint: ring0 process working
-
-- VFS layer (open/read/write/...) with USTar filesystem (for initrd)
-
-** Checkpoint: files not linked to but accessible by the kernel
-
-- Ring3 memory mappings 
-- Ring3 privilege switch
-
-** Checkpoint: welcome to userland
-
-- Syscall interface
-- Implement syscalls needed for doom
-
-** Checkpoint: can run simple programs, ring 3, loaded from filesystem 
-
-- Properly handle the keyboard interrupt (keyboard buffer)
-- Port DOOMgeneric (few functions with Framebuffer/ticks/etc.)
-
-** Achievement: It runs doom!

Makefile

@@ -1,16 +1,21 @@
 SOURCES = src/debug/misc.c src/io/term/flanterm_backends/fb.c src/io/term/flanterm.c src/debug/panic.c src/debug/stacktrace.c src/boot/boot.c src/sched/scheduler.c src/sched/process.c src/mem/heap/kheap.c src/mem/paging/vmm.c src/mem/paging/paging.c src/mem/paging/pmm.c src/string/string.c src/io/kbd/ps2.c src/io/serial/serial.c src/io/term/printf.c src/io/term/term.c src/idt/idt.c src/mem/gdt/gdt.c src/mem/misc/utils.c src/time/timer.c src/kmain.c
 
-PROBLEMATIC_FLAGS=-Wno-unused-parameter -Wno-unused-variable
+CC_FLAGS=-Wall -Wextra -std=gnu99 -nostdlib -ffreestanding -fno-stack-protector -fno-omit-frame-pointer -fno-stack-check -fno-PIC -ffunction-sections -fdata-sections -mcmodel=kernel
+CC_PROBLEMATIC_FLAGS=-Wno-unused-parameter -Wno-unused-variable
+
+.PHONY: build build-iso debug debug2 run clean
 
 build:
-	rm -f *.o
+	mkdir -p build
-	x86_64-elf-gcc -g -c -Isrc $(SOURCES) $(PROBLEMATIC_FLAGS) -Wall -Wextra -std=gnu99 -nostdlib -ffreestanding -fno-stack-protector -fno-omit-frame-pointer -fno-stack-check -fno-PIC -ffunction-sections -fdata-sections -mcmodel=kernel
+	rm -f *.o build/*.o
-	nasm -f elf64 src/idt/idt.S -o idt_stub.o
+	x86_64-elf-gcc -g -c -Isrc $(SOURCES) $(CC_PROBLEMATIC_FLAGS) $(CC_FLAGS)
-	x86_64-elf-ld -o pepperk -T linker.ld *.o
+	mv *.o build/
+	nasm -f elf64 src/idt/idt.S -o build/idt_stub.o
+	x86_64-elf-ld -o pepperk -T linker.ld build/*.o
 	nm -n pepperk | awk '$$2 ~ /[TtDdBbRr]/ {print $$1, $$3}' > symbols.map
 	python3 symbols.py
-	nasm -f elf64 symbols.S -o symbols.o
+	nasm -f elf64 symbols.S -o build/symbols.o
-	x86_64-elf-ld -o pepperk -T linker.ld *.o
+	x86_64-elf-ld -o pepperk -T linker.ld build/*.o
 
 limine/limine:
 	rm -rf limine
@@ -46,4 +51,4 @@ run: build-iso
 	/usr/bin/qemu-system-x86_64 -cdrom pepper.iso -serial stdio
 
 clean:
-	rm -rf *.o symbols.map symbols.S pepperk iso_root pepper.iso limine
+	rm -rf *.o symbols.map symbols.S pepperk iso_root pepper.iso limine build/*.o

docs/STYLE.md

@@ -0,0 +1,83 @@
+# Pepper kernel coding style
+
+This document describes the coding style for the Pepper kernel. It is used as a guideline across all source files.
+
+## Indentation
+
+Indentations should be 4 characters long.
+
+## Line length
+
+Lines should not be more than 100 characters long.
+
+## Variables
+
+Variables should be declared at most once per line.
+
+## Braces
+
+Non-function statement blocks should have an opening brace last on the line, and a closing brace first. Exception is made for `else`, `else if` statements and the like:
+
+```c
+if (something) {
+    do_something();
+} else if (something_else) {
+    do_something_else();
+}
+```
+
+Functions should have their opening brace on a separate line, and the same goes for the closing brace:
+
+```c
+void function()
+{
+    do_something();
+}
+```
+
+## Spaces
+
+Use a space after `if, switch, case, for, do, while` keywords, but not for `sizeof, typeof, alignof, __attribute__` and the like.
+
+For pointers, the asterisk should always be placed adjacent to the type name, like `char* str;`.
+
+## Naming
+
+Functions should be named with whole words, beginning with the corresponding name of the module in the kernel (the parent folder). Words should be spaced with underscores, like so:
+
+```c
+serial_init(void* ptr, char* str, int foo);
+```
+
+Constants should be named in all caps, separated by underscores:
+
+```c
+#define MAX_HEAP_SIZE 0x1000
+```
+
+Global variables need to have descriptive names. Local variables can be kept short (especially for loop counters).
+
+## Typedefs
+
+Structures should not be `typedef`'d.
+
+## Functions
+
+Functions should be short, simple, and only do one thing.
+
+Function prototypes should include parameter names and their data types.
+
+## Commenting
+
+Comments should describe what a function does and why, not how it does it.
+
+```c
+/*
+ * This is the preferred style for multi-line
+ * comments in the Pepper kernel
+ */
+```
+
+### Resources
+
+Some of the elements here are inspired by the [Linux kernel coding style](https://www.kernel.org/doc/html/v4.10/process/coding-style.html).

src/debug/panic.c

@@ -3,6 +3,8 @@
 #include "io/serial/serial.h"
 #include "kernel.h"
 
+extern struct init_status init;
+
 void panic(struct cpu_status_t* ctx, const char* str)
 {
 	CLEAR_INTERRUPTS;
@@ -15,6 +17,13 @@ void panic(struct cpu_status_t* ctx, const char* str)
 		skputc('\r');
 		skputc('\n');
 		DEBUG("\x1b[38;5;231m\x1b[48;5;196mend Kernel panic - halting...\x1b[0m");
+
+		if (init.terminal)
+		{
+			printf("\r\n\x1b[38;5;231m\x1b[48;5;196mKernel panic!!!\x1b[0m Something went horribly wrong! (no cpu ctx)");
+			printf("\r\n%s\r\n\x1b[38;5;231m\x1b[48;5;196mend Kernel panic - halting...\x1b[0m", str);
+		}
+
 		hcf();
 	}
 	DEBUG("\x1b[38;5;231m\x1b[48;5;196mKernel panic!!!\x1b[0m at rip=%p\r\nSomething went horribly wrong! (%s) vect=0x%.2x errcode=0x%x\n\rrax=%p rbx=%p rcx=%p rdx=%p\n\rrsi=%p rdi=%p  r8=%p  r9=%p\n\rr10=%p r11=%p r12=%p r13=%p\n\rr14=%p r15=%p\n\n\rflags=%p\n\rHalting...",
@@ -22,6 +31,17 @@ void panic(struct cpu_status_t* ctx, const char* str)
 		str,
 		ctx->vector_number, ctx->error_code, ctx->rax, ctx->rbx, ctx->rcx, ctx->rdx, ctx->rsi, ctx->rdi,
 		ctx->r8, ctx->r9, ctx->r10, ctx->r11, ctx->r12, ctx->r13, ctx->r14, ctx->r15, ctx->iret_flags);
+	
+	if (init.terminal)
+	{
+		printf("\r\n\x1b[38;5;231m\x1b[48;5;196mKernel panic!!!\x1b[0m at rip=%p\r\nSomething went horribly wrong! (%s) vect=0x%.2x errcode=0x%x\n\rrax=%p rbx=%p rcx=%p rdx=%p\n\rrsi=%p rdi=%p  r8=%p  r9=%p\n\rr10=%p r11=%p r12=%p r13=%p\n\rr14=%p r15=%p\n\n\rflags=%p\n\rHalting...",
+		ctx->iret_rip,
+		str,
+		ctx->vector_number, ctx->error_code, ctx->rax, ctx->rbx, ctx->rcx, ctx->rdx, ctx->rsi, ctx->rdi,
+		ctx->r8, ctx->r9, ctx->r10, ctx->r11, ctx->r12, ctx->r13, ctx->r14, ctx->r15, ctx->iret_flags);
+	}
+	
 	debug_stack_trace(100);
+	
 	hcf();
 }

src/debug/stacktrace.c

@@ -1,9 +1,15 @@
 #include <stdint.h>
 #include "kernel.h"
 
+extern struct init_status init;
+
 void debug_stack_trace(unsigned int max_frames)
 {
     DEBUG("*** begin stack trace ***");
+    if (init.terminal)
+    {
+        printf("\r\n*** begin stack trace ***\r\n");
+    }
     // Thanks GCC :)
     uintptr_t* rbp = (uintptr_t*)__builtin_frame_address(0);
 
@@ -15,6 +21,11 @@ void debug_stack_trace(unsigned int max_frames)
         const char* name = debug_find_symbol(rip, &offset);
         DEBUG("[%u] <0x%p> (%s+0x%x)", frame, (void*)rip, name, offset);
 
+        if (init.terminal)
+        {
+            printf("[%u] <0x%p> (%s+0x%x)\r\n", frame, (void*)rip, name, offset);
+        }
+
         uintptr_t* next_rbp = (uintptr_t*)rbp[0];
 
         // invalid rbp or we're at the end
@@ -25,6 +36,10 @@ void debug_stack_trace(unsigned int max_frames)
 
         rbp = next_rbp;
     }
+    if (init.terminal)
+    {
+        printf("*** end stack trace ***");
+    }
     DEBUG("*** end stack trace ***");
 }
 

src/kmain.c

@@ -57,6 +57,7 @@ bool iran = false;
 // Never gets executed although pedicel is scheduled?
 void pedicel_main(void* arg)
 {
+	//panic(NULL, "test");
 	bool iran = true;
 	// FROM THE NEXT LINE ONWARDS, CANNOT WRITE TO FRAMEBUFFER WITHOUT PAGE FAULT!
 	//printf("\n\nWelcome to PepperOS! Pedicel speaking.\nNothing left to do, halting the system!");

test.bin

@@ -1 +0,0 @@
-ｸ�ｭﾞ�