HelenOS sources

root/uspace/app/bdsh/input.c

DEFINITIONS

1. find_alias_hup
2. process_input_nohup
3. process_input
4. print_pipe_usage
5. run_command
6. get_input
7. input_init

/*
 * Copyright (c) 2008 Tim Post
 * Copyright (c) 2011 Jiri Svoboda
 * Copyright (c) 2011 Martin Sucha
 * Copyright (c) 2018 Matthieu Riolo
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * - Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 * - The name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include <stdio.h>
#include <stdlib.h>
#include <str.h>
#include <io/console.h>
#include <io/keycode.h>
#include <io/style.h>
#include <io/color.h>
#include <vfs/vfs.h>
#include <clipboard.h>
#include <macros.h>
#include <errno.h>
#include <assert.h>
#include <stdbool.h>
#include <tinput.h>
#include <adt/odict.h>
#include <adt/list.h>

#include "config.h"
#include "compl.h"
#include "util.h"
#include "scli.h"
#include "input.h"
#include "errors.h"
#include "exec.h"
#include "tok.h"

extern volatile unsigned int cli_quit;

/** Text input field. */
static tinput_t *tinput;

/* Private helpers */
static int run_command(char **, cliuser_t *, iostate_t *);
static void print_pipe_usage(void);

typedef struct {
        link_t alias_hup_link;
        alias_t *alias;
} alias_hup_t;

static bool find_alias_hup(alias_t *alias, list_t *alias_hups)
{
        list_foreach(*alias_hups, alias_hup_link, alias_hup_t, link) {
                if (alias == link->alias) {
                        return true;
                }
        }

        return false;
}

/*
 * Tokenizes input from console, sees if the first word is a built-in, if so
 * invokes the built-in entry point (a[0]) passing all arguments in a[] to
 * the handler
 */
static errno_t process_input_nohup(cliuser_t *usr, list_t *alias_hups, size_t count_executed_hups)
{
        if (count_executed_hups >= HUBS_MAX) {
                cli_error(CL_EFAIL, "%s: maximal alias hubs reached\n", PACKAGE_NAME);
                return ELIMIT;
        }

        token_t *tokens_buf = calloc(WORD_MAX, sizeof(token_t));
        if (tokens_buf == NULL)
                return ENOMEM;
        token_t *tokens = tokens_buf;

        char *cmd[WORD_MAX];
        errno_t rc = EOK;
        tokenizer_t tok;
        unsigned int i, pipe_count, processed_pipes;
        unsigned int pipe_pos[2];
        char *redir_from = NULL;
        char *redir_to = NULL;

        if (usr->line == NULL) {
                free(tokens_buf);
                return EINVAL;
        }

        rc = tok_init(&tok, usr->line, tokens, WORD_MAX);
        if (rc != EOK) {
                goto finit;
        }

        size_t tokens_length;
        rc = tok_tokenize(&tok, &tokens_length);
        if (rc != EOK) {
                goto finit;
        }

        if (tokens_length > 0 && tokens[0].type == TOKTYPE_SPACE) {
                tokens++;
                tokens_length--;
        }

        if (tokens_length > 0 && tokens[tokens_length - 1].type == TOKTYPE_SPACE) {
                tokens_length--;
        }

        /*
         * Until full support for pipes is implemented, allow for a simple case:
         * [from <file> |] command [| to <file>]
         *
         * First find the pipes and check that there are no more
         */
        for (i = 0, pipe_count = 0; i < tokens_length; i++) {
                if (tokens[i].type == TOKTYPE_PIPE) {
                        if (pipe_count >= 2) {
                                print_pipe_usage();
                                rc = ENOTSUP;
                                goto finit;
                        }
                        pipe_pos[pipe_count] = i;
                        pipe_count++;
                }
        }

        unsigned int cmd_token_start = 0;
        unsigned int cmd_token_end = tokens_length;

        processed_pipes = 0;

        /* Check if the first part (from <file> |) is present */
        if (pipe_count > 0 && (pipe_pos[0] == 3 || pipe_pos[0] == 4) && str_cmp(tokens[0].text, "from") == 0) {
                /* Ignore the first three tokens (from, file, pipe) and set from */
                redir_from = tokens[2].text;
                cmd_token_start = pipe_pos[0] + 1;
                processed_pipes++;
        }

        /* Check if the second part (| to <file>) is present */
        if ((pipe_count - processed_pipes) > 0 &&
            (pipe_pos[processed_pipes] == tokens_length - 4 ||
            (pipe_pos[processed_pipes] == tokens_length - 5 &&
            tokens[tokens_length - 4].type == TOKTYPE_SPACE)) &&
            str_cmp(tokens[tokens_length - 3].text, "to") == 0) {
                /* Ignore the last three tokens (pipe, to, file) and set to */
                redir_to = tokens[tokens_length - 1].text;
                cmd_token_end = pipe_pos[processed_pipes];
                processed_pipes++;
        }

        if (processed_pipes != pipe_count) {
                print_pipe_usage();
                rc = ENOTSUP;
                goto finit;
        }

        /* Convert tokens of the command to string array */
        unsigned int cmd_pos = 0;
        for (i = cmd_token_start; i < cmd_token_end; i++) {
                if (tokens[i].type != TOKTYPE_SPACE) {
                        cmd[cmd_pos++] = tokens[i].text;
                }
        }
        cmd[cmd_pos++] = NULL;

        if (cmd[0] == NULL) {
                print_pipe_usage();
                rc = ENOTSUP;
                goto finit;
        }

        /* test if the passed cmd is an alias */
        odlink_t *alias_link = odict_find_eq(&alias_dict, (void *)cmd[0], NULL);
        if (alias_link != NULL) {
                alias_t *data = odict_get_instance(alias_link, alias_t, odict);
                /* check if the alias already has been resolved once */
                if (!find_alias_hup(data, alias_hups)) {
                        alias_hup_t *hup = (alias_hup_t *)calloc(1, sizeof(alias_hup_t));
                        if (hup == NULL) {
                                cli_error(CL_EFAIL, "%s: cannot allocate alias structure\n", PACKAGE_NAME);
                                rc = ENOMEM;
                                goto finit;
                        }

                        hup->alias = data;
                        list_append(&hup->alias_hup_link, alias_hups);

                        char *oldLine = usr->line;
                        const size_t input_length = str_size(usr->line) - str_size(cmd[0]) + str_size(data->value) + 1;
                        usr->line = (char *)malloc(input_length);
                        if (usr->line == NULL) {
                                cli_error(CL_EFAIL, "%s: cannot allocate input structure\n", PACKAGE_NAME);
                                rc = ENOMEM;
                                goto finit;
                        }

                        usr->line[0] = '\0';

                        unsigned int cmd_replace_index = cmd_token_start;
                        for (i = 0; i < tokens_length; i++) {
                                if (i == cmd_replace_index) {
                                        /* if there is a pipe symbol than cmd_token_start will point at the SPACE after the pipe symbol */
                                        if (tokens[i].type == TOKTYPE_SPACE) {
                                                cmd_replace_index++;
                                                str_append(usr->line, input_length, tokens[i].text);
                                                continue;
                                        }

                                        str_append(usr->line, input_length, data->value);
                                } else {
                                        str_append(usr->line, input_length, tokens[i].text);
                                }
                        }

                        /* reprocess input after string replace */
                        rc = process_input_nohup(usr, alias_hups, count_executed_hups + 1);
                        usr->line = oldLine;
                        goto finit;
                }
        }

        iostate_t new_iostate = {
                .stdin = stdin,
                .stdout = stdout,
                .stderr = stderr
        };

        FILE *from = NULL;
        FILE *to = NULL;

        if (redir_from) {
                from = fopen(redir_from, "r");
                if (from == NULL) {
                        printf("Cannot open file %s\n", redir_from);
                        rc = errno;
                        goto finit_with_files;
                }
                new_iostate.stdin = from;
        }

        if (redir_to) {
                to = fopen(redir_to, "w");
                if (to == NULL) {
                        printf("Cannot open file %s\n", redir_to);
                        rc = errno;
                        goto finit_with_files;
                }
                new_iostate.stdout = to;
        }

        if (run_command(cmd, usr, &new_iostate) == 0) {
                rc = EOK;
        } else {
                rc = EINVAL;
        }

finit_with_files:
        if (from != NULL) {
                fclose(from);
        }
        if (to != NULL) {
                fclose(to);
        }

finit:
        if (NULL != usr->line) {
                free(usr->line);
                usr->line = (char *) NULL;
        }
        tok_fini(&tok);
        free(tokens_buf);

        return rc;
}

errno_t process_input(cliuser_t *usr)
{
        list_t alias_hups;
        list_initialize(&alias_hups);

        errno_t rc = process_input_nohup(usr, &alias_hups, 0);

        list_foreach_safe(alias_hups, cur_link, next_link) {
                alias_hup_t *cur_item = list_get_instance(cur_link, alias_hup_t, alias_hup_link);
                free(cur_item);
        }

        return rc;
}

void print_pipe_usage(void)
{
        printf("Invalid syntax!\n");
        printf("Usage of redirection (pipes in the future):\n");
        printf("from filename | command ...\n");
        printf("from filename | command ... | to filename\n");
        printf("command ... | to filename\n");

}

int run_command(char **cmd, cliuser_t *usr, iostate_t *new_iostate)
{
        int id = 0;

        /* We have rubbish */
        if (NULL == cmd[0]) {
                return CL_ENOENT;
        }

        /* Is it a builtin command ? */
        if ((id = (is_builtin(cmd[0]))) > -1) {
                return run_builtin(id, cmd, usr, new_iostate);
        }

        /* Is it a module ? */
        if ((id = (is_module(cmd[0]))) > -1) {
                return run_module(id, cmd, new_iostate);
        }

        /* See what try_exec thinks of it */
        return try_exec(cmd[0], cmd, new_iostate);
}

void get_input(cliuser_t *usr)
{
        char *str;
        errno_t rc;

        tinput_set_prompt(tinput, usr->prompt);

        rc = tinput_read(tinput, &str);
        if (rc == ENOENT) {
                /* User requested exit */
                cli_quit = 1;
                putchar('\n');
                return;
        }

        if (rc != EOK) {
                /* Error in communication with console */
                cli_quit = 1;
                return;
        }

        /* Check for empty input. */
        if (str_cmp(str, "") == 0) {
                free(str);
                return;
        }

        usr->line = str;
        return;
}

int input_init(void)
{
        tinput = tinput_new();
        if (tinput == NULL) {
                printf("Failed to initialize input.\n");
                return 1;
        }

        tinput_set_compl_ops(tinput, &compl_ops);

        return 0;
}