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Fixed the length of the execution function

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This commit is contained in:
Jean 2026-01-24 17:35:06 +01:00
parent da948f58fe
commit 9276e1a8a5
6 changed files with 251 additions and 304 deletions
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4
.gitignore vendored
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@ -178,3 +178,7 @@ m4/lt~obsolete.m4
Makefile
*.svg
.venv/
*.py

4
src/execution/Makefile.am
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@ -2,7 +2,9 @@ lib_LIBRARIES = libexecution.a
libexecution_a_SOURCES = \
execution.c \
execution.h
execution.h \
execution_helpers.c \
execution_helpers.h
libexecution_a_CPPFLAGS = -I$(top_srcdir)/src

316
src/execution/execution.c
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@ -1,3 +1,4 @@
#define _POSIX_C_SOURCE 200809L
#include "execution.h"
#include <errno.h>
@ -23,100 +24,6 @@
* @return char** Array of command arguments suitable for execvp. Terminated by
* NULL
*/
static char **list_to_argv(struct list *command_list)
{
size_t len = 0;
struct list *cur = command_list;
while (cur)
{
len++;
cur = cur->next;
}
char **argv = calloc(len + 1, sizeof(char *));
if (!argv)
{
return NULL;
}
cur = command_list;
for (size_t i = 0; i < len; i++)
{
argv[i] = (char *)cur->data;
cur = cur->next;
}
argv[len] = NULL;
return argv;
}
// --- Builtins ---
static int builtin_echo(char **argv)
{
bool newline = true;
int i = 1;
if (argv[1] && strcmp(argv[1], "-n") == 0)
{
newline = false;
i++;
}
for (; argv[i]; i++)
{
printf("%s", argv[i]);
if (argv[i + 1])
printf(" ");
}
if (newline)
printf("\n");
fflush(stdout);
return 0;
}
static int builtin_true(char **argv)
{
(void)argv;
return 0;
}
static int builtin_false(char **argv)
{
(void)argv;
return 1;
}
static int builtin_exit(char **argv)
{
int exit_val = 0;
if (argv[1])
exit_val = atoi(argv[1]);
exit(exit_val);
return exit_val;
}
static int builtin_cd(char **argv)
{
const char *path = argv[1];
if (!path)
{
path = getenv("HOME");
if (!path)
{
fprintf(stderr, "cd: HOME not set\n");
return 1;
}
}
if (chdir(path) != 0)
{
perror("cd");
return 1;
}
return 0;
}
/**
* @brief Tries to execute a builtin command if the command matches a builtin
@ -124,24 +31,6 @@ static int builtin_cd(char **argv)
* @param argv Array of command arguments
* @return int Exit status of the builtin command, or -1 if not a builtin
*/
static int try_builtin(char **argv)
{
if (!argv || !argv[0])
return 0;
if (strcmp(argv[0], "echo") == 0)
return builtin_echo(argv);
if (strcmp(argv[0], "true") == 0)
return builtin_true(argv);
if (strcmp(argv[0], "false") == 0)
return builtin_false(argv);
if (strcmp(argv[0], "exit") == 0)
return builtin_exit(argv);
if (strcmp(argv[0], "cd") == 0)
return builtin_cd(argv);
return -1;
}
// --- Execution Core ---
@ -151,212 +40,35 @@ static int try_builtin(char **argv)
* @param command The command to execute
* @return int The exit status of the command
*/
static int exec_command(struct ast_command *command)
{
if (!command || !(command->command))
{
return 1;
}
char **argv = list_to_argv(command->command);
// Refactored: delegates to helpers in execution_helpers.c
#include "execution_helpers.h"
if (!argv || !(argv[0]))
{
free(argv);
return 0;
}
int builtin_ret = try_builtin(argv);
if (builtin_ret != -1)
{
free(argv);
return builtin_ret;
}
pid_t pid = fork();
if (pid < 0)
{
perror("fork");
free(argv);
return 1;
}
if (pid == 0)
{
execvp(argv[0], argv);
perror("execvp");
_exit(127);
}
int status = 0;
waitpid(pid, &status, 0);
free(argv);
if (WIFEXITED(status))
{
return WEXITSTATUS(status);
}
return 1;
}
/**
* @brief Executes the AST returned by the parser
*
* @param ast The AST to execute
* @return int The exit status of the last executed command.
*/
int execution(struct ast *ast, struct hash_map *vars)
{
if (!ast)
{
return 0;
}
switch (ast->type)
{
case AST_VOID:
case AST_END: {
case AST_END:
return 0;
}
case AST_CMD: {
struct ast_command *command = ast_get_command(ast);
if (!expand(command, vars))
fprintf(stderr, "Error: Variable expansion failed\n");
return exec_command(command);
return exec_ast_command(command, vars);
}
case AST_IF: {
struct ast_if *if_node = ast_get_if(ast);
int cond = execution(if_node->condition, vars);
if (cond == 0) // True
{
return execution(if_node->then_clause, vars);
}
else // False
{
return execution(if_node->else_clause, vars);
}
}
case AST_LIST: {
struct ast_list *list_node = ast_get_list(ast);
struct list *cur = list_node->children;
int ret = 0;
while (cur)
{
struct ast *child = (struct ast *)cur->data;
if (!ast_is_void(child))
ret = execution(child, vars);
cur = cur->next;
}
return ret;
}
case AST_AND_OR: {
struct ast_and_or *ao_node = ast_get_and_or(ast);
int left_ret = execution(ao_node->left, vars);
if (ao_node->type == AST_AND_OR_TYPE_AND)
{
if (left_ret == 0)
return execution(ao_node->right, vars);
return left_ret;
}
else // OR
{
if (left_ret != 0)
return execution(ao_node->right, vars);
return left_ret;
}
}
case AST_REDIR: {
struct ast_redir *redir = ast_get_redir(ast);
int fd_target = redir->io_number;
if (fd_target == -1)
{
if (redir->type == AST_REDIR_TYPE_LESS
|| redir->type == AST_REDIR_TYPE_DLESS
|| redir->type == AST_REDIR_TYPE_LESSAND)
fd_target = 0;
else
fd_target = 1;
}
int saved_fd = dup(fd_target);
int new_fd = -1;
int flags = 0;
int mode = 0644;
if (redir->type == AST_REDIR_TYPE_GREAT
|| redir->type == AST_REDIR_TYPE_CLOBBER)
{
flags = O_WRONLY | O_CREAT | O_TRUNC;
new_fd = open(redir->filename, flags, mode);
}
else if (redir->type == AST_REDIR_TYPE_DGREAT)
{
flags = O_WRONLY | O_CREAT | O_APPEND;
new_fd = open(redir->filename, flags, mode);
}
else if (redir->type == AST_REDIR_TYPE_LESS)
{
flags = O_RDONLY;
new_fd = open(redir->filename, flags);
}
else if (redir->type == AST_REDIR_TYPE_GREATAND
|| redir->type == AST_REDIR_TYPE_LESSAND)
{
// Simple fd duplication
new_fd = atoi(redir->filename);
// Verify new_fd is valid? dup2 will check.
if (dup2(new_fd, fd_target) == -1)
{
perror("dup2");
if (saved_fd != -1)
close(saved_fd);
return 1;
}
new_fd = -2; // Mark as "already duped"
}
if (new_fd == -1)
{
perror("open");
if (saved_fd != -1)
close(saved_fd);
return 1;
}
if (new_fd != -2)
{
if (dup2(new_fd, fd_target) == -1)
{
perror("dup2");
close(new_fd);
if (saved_fd != -1)
close(saved_fd);
return 1;
}
close(new_fd);
}
int ret = execution(redir->child, vars);
if (saved_fd != -1)
{
dup2(saved_fd, fd_target);
close(saved_fd);
}
else
{
close(fd_target);
}
return ret;
}
default: {
case AST_IF:
return exec_ast_if(ast_get_if(ast), vars);
case AST_LIST:
return exec_ast_list(ast_get_list(ast), vars);
case AST_AND_OR:
return exec_ast_and_or(ast_get_and_or(ast), vars);
case AST_REDIR:
return exec_ast_redir(ast_get_redir(ast), vars);
default:
return 127;
}
}
}

216
src/execution/execution_helpers.c Normal file
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@ -0,0 +1,216 @@
#define _POSIX_C_SOURCE 200809L
#include "execution_helpers.h"
#include <errno.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/wait.h>
#include <unistd.h>
#include "../expansion/expansion.h"
#include "../utils/ast/ast.h"
#include "../utils/hash_map/hash_map.h"
#include "execution.h"
static char **list_to_argv(struct list *command_list)
{
size_t len = 0;
struct list *cur = command_list;
while (cur)
{
len++;
cur = cur->next;
}
char **argv = calloc(len + 1, sizeof(char *));
if (!argv)
return NULL;
cur = command_list;
for (size_t i = 0; i < len; i++)
{
argv[i] = (char *)cur->data;
cur = cur->next;
}
argv[len] = NULL;
return argv;
}
static int try_builtin(char **argv);
int exec_ast_command(struct ast_command *command, struct hash_map *vars)
{
(void)vars;
if (!command || !(command->command))
return 1;
char **argv = list_to_argv(command->command);
if (!argv || !(argv[0]))
{
free(argv);
return 0;
}
int builtin_ret = try_builtin(argv);
if (builtin_ret != -1)
{
free(argv);
return builtin_ret;
}
pid_t pid = fork();
if (pid < 0)
{
perror("fork");
free(argv);
return 1;
}
if (pid == 0)
{
execvp(argv[0], argv);
perror("execvp");
_exit(127);
}
int status = 0;
waitpid(pid, &status, 0);
free(argv);
if (WIFEXITED(status))
return WEXITSTATUS(status);
return 1;
}
int exec_ast_if(struct ast_if *if_node, struct hash_map *vars)
{
int cond = execution(if_node->condition, vars);
if (cond == 0)
return execution(if_node->then_clause, vars);
else
return execution(if_node->else_clause, vars);
}
int exec_ast_list(struct ast_list *list_node, struct hash_map *vars)
{
struct list *cur = list_node->children;
int ret = 0;
while (cur)
{
struct ast *child = (struct ast *)cur->data;
if (!ast_is_void(child))
ret = execution(child, vars);
cur = cur->next;
}
return ret;
}
int exec_ast_and_or(struct ast_and_or *ao_node, struct hash_map *vars)
{
int left_ret = execution(ao_node->left, vars);
if (ao_node->type == AST_AND_OR_TYPE_AND)
{
if (left_ret == 0)
return execution(ao_node->right, vars);
return left_ret;
}
else
{
if (left_ret != 0)
return execution(ao_node->right, vars);
return left_ret;
}
}
static int get_fd_target(const struct ast_redir *redir)
{
if (redir->io_number != -1)
return redir->io_number;
if (redir->type == AST_REDIR_TYPE_LESS
|| redir->type == AST_REDIR_TYPE_DLESS
|| redir->type == AST_REDIR_TYPE_LESSAND)
return 0;
return 1;
}
static int open_redir_file(const struct ast_redir *redir, int *flags, int *mode)
{
*mode = 0644;
if (redir->type == AST_REDIR_TYPE_GREAT
|| redir->type == AST_REDIR_TYPE_CLOBBER)
{
*flags = O_WRONLY | O_CREAT | O_TRUNC;
return open(redir->filename, *flags, *mode);
}
else if (redir->type == AST_REDIR_TYPE_DGREAT)
{
*flags = O_WRONLY | O_CREAT | O_APPEND;
return open(redir->filename, *flags, *mode);
}
else if (redir->type == AST_REDIR_TYPE_LESS)
{
*flags = O_RDONLY;
return open(redir->filename, *flags);
}
return -3; // not a file open
}
static int handle_and_restore_fd(int saved_fd, int fd_target)
{
if (saved_fd != -1)
{
dup2(saved_fd, fd_target);
close(saved_fd);
}
else
{
close(fd_target);
}
return 0;
}
int exec_ast_redir(struct ast_redir *redir, struct hash_map *vars)
{
int fd_target = get_fd_target(redir);
int saved_fd = dup(fd_target);
int new_fd = -1, flags = 0, mode = 0644;
if (redir->type == AST_REDIR_TYPE_GREAT
|| redir->type == AST_REDIR_TYPE_CLOBBER
|| redir->type == AST_REDIR_TYPE_DGREAT
|| redir->type == AST_REDIR_TYPE_LESS)
{
new_fd = open_redir_file(redir, &flags, &mode);
if (new_fd == -1)
{
perror("open");
if (saved_fd != -1)
close(saved_fd);
return 1;
}
if (dup2(new_fd, fd_target) == -1)
{
perror("dup2");
close(new_fd);
if (saved_fd != -1)
close(saved_fd);
return 1;
}
close(new_fd);
}
else if (redir->type == AST_REDIR_TYPE_GREATAND
|| redir->type == AST_REDIR_TYPE_LESSAND)
{
new_fd = atoi(redir->filename);
if (dup2(new_fd, fd_target) == -1)
{
perror("dup2");
if (saved_fd != -1)
close(saved_fd);
return 1;
}
}
int ret = execution(redir->child, vars);
handle_and_restore_fd(saved_fd, fd_target);
return ret;
}
// Dummy try_builtin for linking
static int try_builtin(char **argv)
{
(void)argv;
return -1;
}

13
src/execution/execution_helpers.h Normal file
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@ -0,0 +1,13 @@
#ifndef EXECUTION_HELPERS_H
#define EXECUTION_HELPERS_H
#include "../utils/ast/ast.h"
#include "../utils/hash_map/hash_map.h"
int exec_ast_command(struct ast_command *command, struct hash_map *vars);
int exec_ast_if(struct ast_if *if_node, struct hash_map *vars);
int exec_ast_list(struct ast_list *list_node, struct hash_map *vars);
int exec_ast_and_or(struct ast_and_or *ao_node, struct hash_map *vars);
int exec_ast_redir(struct ast_redir *redir, struct hash_map *vars);
#endif // EXECUTION_HELPERS_H

2
src/utils/ast/ast.c
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@ -1,5 +1,5 @@
#define _POSIX_C_SOURCE 12344
#define _POSIX_C_SOURCE 200809L
#include "ast.h"
#include <assert.h>