diretórios 8 e 13 de exemplos

curso/exemplos/13/teste.asm

@@ -0,0 +1,146 @@
+; Arquivo: pipe_ls_cat.asm
+; Montar com: nasm -felf64 pipe_ls_cat.asm && ld -o pipe_ls_cat pipe_ls_cat.o
+
+%define SYS_READ    0
+%define SYS_WRITE   1
+%define SYS_CLOSE   3
+%define SYS_PIPE    22
+%define SYS_DUP2    33
+%define SYS_FORK    57
+%define SYS_EXECVE  59
+%define SYS_EXIT    60
+%define SYS_WAITPID 61
+
+%define STDIN_FD    0
+%define STDOUT_FD   1
+%define STDERR_FD   2
+
+%define EXIT_SUCCESS 0
+%define EXIT_FAILURE 1
+
+section .rodata
+    cmd_ls     db "/bin/ls", 0
+    arg0_ls    dq cmd_ls
+    arg1_ls    db "-l", 0
+    arg2_ls    db "/proc/self/fd", 0
+    argv_ls    dq arg0_ls, arg1_ls, arg2_ls, 0
+
+    cmd_cat    db "/bin/cat", 0
+    arg0_cat   dq cmd_cat
+    argv_cat   dq arg0_cat, 0
+
+    envp_null  dq 0
+
+section .bss
+    pipefds resq 2   ; 2 x 8 bytes (r/w)
+
+section .text
+global _start
+
+_start:
+    ; Cria pipe
+    mov     rax, SYS_PIPE
+    mov     rdi, pipefds
+    syscall
+
+    mov     r12, [pipefds]       ; leitura (pipefds[0])
+    mov     r13, [pipefds + 8]   ; escrita (pipefds[1])
+
+    ; Fork para ls
+    mov     rax, SYS_FORK
+    syscall
+    test    rax, rax
+    jz      .ls_child
+
+    ; Fork para cat
+    mov     rax, SYS_FORK
+    syscall
+    test    rax, rax
+    jz      .cat_child
+
+    ; Pai: fecha descritores do pipe
+    mov     rax, SYS_CLOSE
+    mov     rdi, r12
+    syscall
+
+    mov     rax, SYS_CLOSE
+    mov     rdi, r13
+    syscall
+
+    ; Espera dois filhos
+    xor     rdi, rdi
+    xor     rsi, rsi
+    xor     rdx, rdx
+    mov     rax, SYS_WAITPID
+    syscall
+
+    xor     rdi, rdi
+    xor     rsi, rsi
+    xor     rdx, rdx
+    mov     rax, SYS_WAITPID
+    syscall
+
+    ; Finaliza
+    mov     rax, SYS_EXIT
+    xor     rdi, rdi
+    syscall
+
+; -----------------------------------------
+; Processo filho: ls -l /proc/self/fd
+; -----------------------------------------
+.ls_child:
+    ; Redireciona stdout → pipe[1]
+    mov     rax, SYS_DUP2
+    mov     rdi, r13         ; escrita
+    mov     rsi, STDOUT_FD
+    syscall
+
+    ; Fecha descritores
+    mov     rax, SYS_CLOSE
+    mov     rdi, r12
+    syscall
+    mov     rax, SYS_CLOSE
+    mov     rdi, r13
+    syscall
+
+    ; execve("/bin/ls", ["ls", "-l", "/proc/self/fd"], NULL)
+    mov     rax, SYS_EXECVE
+    mov     rdi, cmd_ls
+    mov     rsi, argv_ls
+    mov     rdx, envp_null
+    syscall
+
+    ; Se execve falhar
+    mov     rax, SYS_EXIT
+    mov     rdi, EXIT_FAILURE
+    syscall
+
+; -----------------------------------------
+; Processo filho: cat
+; -----------------------------------------
+.cat_child:
+    ; Redireciona stdin ← pipe[0]
+    mov     rax, SYS_DUP2
+    mov     rdi, r12         ; leitura
+    mov     rsi, STDIN_FD
+    syscall
+
+    ; Fecha descritores
+    mov     rax, SYS_CLOSE
+    mov     rdi, r12
+    syscall
+    mov     rax, SYS_CLOSE
+    mov     rdi, r13
+    syscall
+
+    ; execve("/bin/cat", ["cat"], NULL)
+    mov     rax, SYS_EXECVE
+    mov     rdi, cmd_cat
+    mov     rsi, argv_cat
+    mov     rdx, envp_null
+    syscall
+
+    ; Se execve falhar
+    mov     rax, SYS_EXIT
+    mov     rdi, EXIT_FAILURE
+    syscall