Subversion Repositories HelenOS

Rev

Rev 4486 | Go to most recent revision | Details | Compare with Previous | Last modification | View Log | RSS feed

Rev Author Line No. Line
3265 post 1
/* Copyright (c) 2008, Tim Post <tinkertim@gmail.com>
2
 * All rights reserved.
3
 *
4
 * Redistribution and use in source and binary forms, with or without
5
 * modification, are permitted provided that the following conditions are met:
6
 *
7
 * Redistributions of source code must retain the above copyright notice, this
8
 * list of conditions and the following disclaimer.
9
 *
10
 * Redistributions in binary form must reproduce the above copyright notice,
11
 * this list of conditions and the following disclaimer in the documentation
12
 * and/or other materials provided with the distribution.
13
 *
14
 * Neither the name of the original program's authors nor the names of its
15
 * contributors may be used to endorse or promote products derived from this
16
 * software without specific prior written permission.
17
 *
18
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
19
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
22
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
23
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
24
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
25
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
26
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
27
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
28
 * POSSIBILITY OF SUCH DAMAGE.
29
 */
30
 
31
/* The VERY basics of execute in place support. These are buggy, leaky
32
 * and not nearly done. Only here for beta testing!! You were warned!!
33
 * TODO:
34
 * Hash command lookups to save time
35
 * Create a running pointer to **path and advance/rewind it as we go */
36
 
37
#include <stdio.h>
38
#include <stdlib.h>
39
#include <unistd.h>
40
#include <string.h>
41
#include <fcntl.h>
42
 
43
#include "config.h"
44
#include "util.h"
45
#include "exec.h"
46
#include "errors.h"
47
 
3340 post 48
/* FIXME: Just have find_command() return an allocated string */
3460 post 49
static char *found;
3265 post 50
 
3372 post 51
static char *find_command(char *);
3460 post 52
static int try_access(const char *);
3372 post 53
 
3265 post 54
/* work-around for access() */
3460 post 55
static int try_access(const char *f)
3265 post 56
{
57
    int fd;
58
 
59
    fd = open(f, O_RDONLY);
3287 post 60
    if (fd > -1) {
3265 post 61
        close(fd);
3287 post 62
        return 0;
3265 post 63
    } else
3287 post 64
        return -1;
3265 post 65
}
66
 
67
/* Returns the full path of "cmd" if cmd is found, else just hand back
68
 * cmd as it was presented */
3372 post 69
static char *find_command(char *cmd)
3265 post 70
{
3366 post 71
    char *path_tok;
3265 post 72
    char *path[PATH_MAX];
3287 post 73
    int n = 0, i = 0;
4264 svoboda 74
    size_t x = str_size(cmd) + 2;
3265 post 75
 
76
    found = (char *)malloc(PATH_MAX);
77
 
3287 post 78
    /* The user has specified a full or relative path, just give it back. */
3304 post 79
    if (-1 != try_access(cmd)) {
3287 post 80
        return (char *) cmd;
81
    }
3265 post 82
 
4266 svoboda 83
    path_tok = str_dup(PATH);
3366 post 84
 
3265 post 85
    /* Extract the PATH env to a path[] array */
3813 post 86
    path[n] = strtok(path_tok, PATH_DELIM);
3265 post 87
    while (NULL != path[n]) {
4264 svoboda 88
        if ((str_size(path[n]) + x ) > PATH_MAX) {
3265 post 89
            cli_error(CL_ENOTSUP,
90
                "Segment %d of path is too large, search ends at segment %d",
91
                n, n-1);
92
            break;
93
        }
3813 post 94
        path[++n] = strtok(NULL, PATH_DELIM);
3265 post 95
    }
96
 
97
    /* We now have n places to look for the command */
98
    for (i=0; path[i]; i++) {
99
        memset(found, 0, sizeof(found));
100
        snprintf(found, PATH_MAX, "%s/%s", path[i], cmd);
3304 post 101
        if (-1 != try_access(found)) {
3265 post 102
            free(path_tok);
103
            return (char *) found;
104
        }
105
    }
106
 
3340 post 107
    /* We didn't find it, just give it back as-is. */
3265 post 108
    free(path_tok);
109
    return (char *) cmd;
110
}
111
 
3340 post 112
unsigned int try_exec(char *cmd, char **argv)
3265 post 113
{
114
    task_id_t tid;
115
    char *tmp;
4617 svoboda 116
    int retval;
3265 post 117
 
4266 svoboda 118
    tmp = str_dup(find_command(cmd));
3265 post 119
    free(found);
120
 
3487 post 121
    tid = task_spawn((const char *)tmp, argv);
3265 post 122
    free(tmp);
123
 
3340 post 124
    if (tid == 0) {
4112 svoboda 125
        cli_error(CL_EEXEC, "Cannot spawn `%s'.", cmd);
3340 post 126
        return 1;
127
    }
4486 decky 128
 
4617 svoboda 129
    task_wait(tid, &retval);
130
    if (retval != 0)
131
        printf("Command failed (return value %d).\n", retval);
132
 
4486 decky 133
    return 0;
3265 post 134
}