From 2c259cd933d502f6db5c178ad6f2a3d83f000302 Mon Sep 17 00:00:00 2001
From: Lucia Ceionia <lucia@noreply.ceionia.com>
Date: Wed, 6 Dec 2023 00:10:38 -0600
Subject: [PATCH] i just.. god..

---
 06/Makefile     |   3 +
 06/input        |   2 +
 06/main.s       |  60 ++++++++++++++++++++
 06/main_part1.s |  53 ++++++++++++++++++
 06/utils.s      | 146 ++++++++++++++++++++++++++++++++++++++++++++++++
 5 files changed, 264 insertions(+)
 create mode 100644 06/Makefile
 create mode 100644 06/input
 create mode 100644 06/main.s
 create mode 100644 06/main_part1.s
 create mode 100644 06/utils.s

diff --git a/06/Makefile b/06/Makefile
new file mode 100644
index 0000000..813998e
--- /dev/null
+++ b/06/Makefile
@@ -0,0 +1,3 @@
+all:
+	nasm -g -felf64 main.s && ld -g main.o
+
diff --git a/06/input b/06/input
new file mode 100644
index 0000000..d7d60a8
--- /dev/null
+++ b/06/input
@@ -0,0 +1,2 @@
+Time:        53     83     72     88
+Distance:   333   1635   1289   1532
diff --git a/06/main.s b/06/main.s
new file mode 100644
index 0000000..c0c5bde
--- /dev/null
+++ b/06/main.s
@@ -0,0 +1,60 @@
+%define BUFF_LIM 32768
+
+global _start
+[bits 64]
+[section .text]
+
+;%include "utils.s"
+
+_start:
+
+xor rcx, rcx ; race
+; check race
+check_race:
+push rcx
+mov rsi, 53837288
+mov rdi, 0x12F02ACD6888C
+;mov rsi, 71530
+;mov rdi, 940200
+;mov rbx, [(dists+4)+rcx*4]
+xor rbp, rbp ; poss
+
+mov rcx, 1 ; test ms
+check_strat:
+mov rax, rsi
+sub rax, rcx ; remaining time
+mul rcx
+;cmp rdx, rbx ; high part
+;jb .cont ; high part is less
+cmp rax, rdi ; low part
+jbe .cont
+inc rbp
+.cont:
+inc rcx
+cmp rcx, rsi
+jl check_strat
+
+mov rax, [final_value]
+mul rbp
+mov [final_value], rax
+
+are_we_done:
+pop rcx
+inc rcx
+cmp rcx, [race_count]
+jl check_race
+
+game_over:
+mov rbx, [final_value]
+jmp $
+
+[section .data]
+final_value: dq 1
+race_count: dq 1
+timelist: dd 53837288
+dists: dq 333163512891532 ; 12F02ACD6888C
+;timelist: dd 71530
+;dists: dq 940200
+
+
+[section .bss]
diff --git a/06/main_part1.s b/06/main_part1.s
new file mode 100644
index 0000000..1542d45
--- /dev/null
+++ b/06/main_part1.s
@@ -0,0 +1,53 @@
+%define BUFF_LIM 32768
+
+global _start
+[bits 32]
+[section .text]
+
+%include "utils.s"
+
+_start:
+
+xor ecx, ecx ; race
+; check race
+check_race:
+push ecx
+mov esi, [timelist+ecx*4]
+mov edi, [dists+ecx*4]
+xor ebp, ebp ; poss
+
+mov ecx, 1 ; test ms
+check_strat:
+mov eax, esi
+sub eax, ecx ; remaining time
+mul ecx
+cmp eax, edi
+jle .cont
+inc ebp
+.cont:
+inc ecx
+cmp ecx, esi
+jl check_strat
+
+mov eax, [final_value]
+mul ebp
+mov [final_value], eax
+
+are_we_done:
+pop ecx
+inc ecx
+cmp ecx, [race_count]
+jl check_race
+
+game_over:
+mov eax, [final_value]
+call print_dec
+jmp exit
+
+[section .data]
+final_value: dd 1
+race_count: dd 4
+timelist: dd 53, 83, 72, 88
+dists: dd 333, 1635, 1289, 1532
+
+[section .bss]
diff --git a/06/utils.s b/06/utils.s
new file mode 100644
index 0000000..a2dbe05
--- /dev/null
+++ b/06/utils.s
@@ -0,0 +1,146 @@
+;             call #  val  val2
+; int $0x80   eax     eax  edx  -
+;
+; arg1  arg2  arg3  arg4  arg5  arg6  arg7  
+; ebx   ecx   edx   esi   edi   ebp   -
+
+exit:
+mov eax, 1 ; exit
+int 0x80
+
+; filename in EBX
+; return handle in EBX 
+; read only
+open_file:
+push eax
+push ecx
+mov eax, 5 ; open
+xor ecx, ecx ; read only
+int 0x80
+mov ebx, eax
+pop ecx
+pop eax
+ret
+
+; file handle in EBX
+; buffer in ECX
+; count of bytes to read in EDX
+; return bytes actually read in EAX
+; exits on error
+read_file:
+mov eax, 3 ; read
+int 0x80
+test eax, eax
+js .err
+ret
+.err:
+mov eax, 4 ; write
+mov ebx, 1 ; stdout
+mov ecx, .err_str
+mov edx, 21
+int 0x80
+jmp exit
+.err_str: db `Could not read file.\n`
+
+; string input in ESI
+; value in EAX
+; CF set if none, clear if some
+; ESI set past checked area
+dec_parse:
+push ebx
+push edx
+push edi
+xor eax, eax
+xor edi, edi
+mov ebx, 10  ; base
+lodsb
+sub al, '0'
+js .no_input
+cmp al, 9
+jle .got_char
+.no_input:
+stc ; set CF
+jmp .done
+.loop:
+xor eax,eax
+lodsb
+sub al, '0'
+js .dec_done
+cmp al, 9
+jg .dec_done
+.got_char:
+xchg edi,eax
+mul ebx
+add edi,eax
+jmp .loop
+.dec_done:
+clc ; clear CF
+.done:
+mov eax,edi
+pop edi
+pop edx
+pop ebx
+ret
+
+; modifies no regs
+newline:
+pushad
+push 10
+mov eax, 4 ; write
+mov ebx, 1 ; stdout
+mov ecx, esp ; string
+mov edx, 1 ; length
+int 0x80
+add esp, 4
+popad
+ret
+; modifies no regs
+space:
+pushad
+push 9
+mov eax, 4 ; write
+mov ebx, 1 ; stdout
+mov ecx, esp ; string
+mov edx, 1 ; length
+int 0x80
+add esp, 4
+popad
+ret
+
+; input in EAX, all regs unmodified
+print_dec:
+pushad ; save regs
+; max 4294967296 is 10 chars
+; round to nearest 32-bit boundary
+sub esp, 12
+; string in ECX, length in EDX
+lea ecx, [esp+11] ; last possible byte
+; check for 0
+test eax, eax
+jz .zero
+mov ebx, 10 ; base 10
+xor esi, esi ; counter
+.div_shit:
+xor edx, edx
+; divide
+div ebx
+dec ecx ; next char
+inc esi
+; store
+add dl, '0'
+mov byte [ecx], dl
+; check if done
+test eax, eax
+jnz .div_shit ; continue
+mov edx, esi ; counter in edx
+jmp .write
+.zero:
+mov byte [ecx], '0'
+mov edx, 1 ; length
+.write:
+mov eax, 4 ; write
+mov ebx, 1 ; stdout
+int 0x80
+add esp, 12 ; restore stack
+popad ; restore regs
+ret