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/*
*
*/
#include "command.h"
#include "config.h"
#include "lexer.h"
#include <stdio.h>
#include <unistd.h>
command *create_command() {
command *cmd = malloc(sizeof(command));
if (!cmd) {
return NULL;
}
cmd->command = NULL;
memset(cmd->args, 0, sizeof(char*));
cmd->pipe[0] = -1;
cmd->pipe[1] = -1;
cmd->read_pipe = NULL;
cmd->infile = NULL;
cmd->outfile = NULL;
cmd->next = NULL;
cmd->pid = 0;
return cmd;
}
command *commands_from_tokens(token *parsed_cmdstr, size_t *cnt) {
command *cmd_head = create_command();
command *cmd = cmd_head;
size_t arg_cnt = 1;
*cnt = 0;
token *prev_tkn = NULL;
for (token *tkn = parsed_cmdstr; tkn; prev_tkn = tkn, tkn = tkn->next) {
if (tkn->type == TKN_COMMAND) {
cmd->command = tkn->text;
cmd->args[0] = tkn->text;
arg_cnt = 1;
(*cnt)++;
} else if (tkn->type == TKN_ARG) {
cmd->args[arg_cnt++] = tkn->text;
} else if (tkn->type == TKN_FILENAME) {
if (prev_tkn->type == TKN_IN_REDIR) {
cmd->infile = tkn->text;
} else {
cmd->outfile = tkn->text;
}
} else if (tkn->type == TKN_PIPE) {
cmd->next = create_command();
cmd->next->read_pipe = cmd->pipe;
cmd = cmd->next;
}
}
return cmd_head;
}
void print_commands(FILE *file, command *cmds) {
for (command *cmd=cmds; cmd; cmd = cmd->next) {
fprintf(file, "Command: %s\n", cmd->command);
fprintf(file, "\t");
for (size_t i=0; i<MAX_ARGUMENT_CNT; i++) {
fprintf(file, "%s ", cmd->args[i]);
}
fprintf(file, "\n\tInfile: %s\n\tOutfile: %s\n\tInput Pipe: %p\n\tPid:%d\n", cmd->infile, cmd->outfile, cmd->read_pipe, cmd->pid);
if (cmd->read_pipe) {
fprintf(file, "\tInput Pipe: %d\n", *cmd->read_pipe);
}
}
}
void destroy_commands(command *cmds) {
command **cmd_ptr = &cmds->next;
while (*cmd_ptr) {
free(cmds);
cmds = *cmd_ptr;
cmd_ptr = &cmds->next;
}
}
pid_t execute_command(command *cmd) {
if (cmd->next) {
pipe(cmd->pipe);
}
pid_t res = fork();
if (res == 0) {
int fdi = -1, fdo = -1;
if (cmd->infile) {
if (!freopen(cmd->infile, "r", stdin)) {
perror("Could not open input file");
exit(EXIT_FAILURE);
}
} else if (cmd->read_pipe && *cmd->read_pipe >= 0) {
fdi = dup2(*(cmd->read_pipe), STDIN_FILENO);
close(*(cmd->read_pipe));
}
if (cmd->outfile) {
if (!freopen(cmd->outfile, "w", stdout)) {
perror("Could not open output file");
exit(EXIT_FAILURE);
}
} else if (cmd->next) {
fdo = dup2(cmd->pipe[1], STDOUT_FILENO);
}
fprintf(stderr, "In command:\n");
fprintf(stderr, "STDIN: %d\tSTDOUT: %d\n", fdi, fdo);
if (cmd->pipe[0] >= 0) {
close(cmd->pipe[0]);
cmd->pipe[0] = -1;
}
if (cmd->pipe[1] >= 0) {
close(cmd->pipe[1]);
cmd->pipe[1] = -1;
}
execvp(cmd->command, cmd->args);
perror("Could not run command");
exit(EXIT_FAILURE);
} else if (res < 0) {
perror("Could not run command");
return -1;
}
cmd->pid = res;
return res;
}
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