WebSVN – HelenOS – Diff – /branches/dynload/uspace/app/bdsh/exec.c


/* Copyright (c) 2008, Tim Post <tinkertim@gmail.com>
 * 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.
 *
 * Neither the name of the original program's authors nor the names of its
 * contributors may be used to endorse or promote products derived from this
 * software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "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 COPYRIGHT OWNER OR CONTRIBUTORS 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.
 */
 
/* The VERY basics of execute in place support. These are buggy, leaky
 * and not nearly done. Only here for beta testing!! You were warned!!
 * TODO:
 * Hash command lookups to save time
 * Create a running pointer to **path and advance/rewind it as we go */
 
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <fcntl.h>
 
#include "config.h"
#include "util.h"
#include "exec.h"
#include "errors.h"
 
/* FIXME: Just have find_command() return an allocated string */
static char *found;
 
static char *find_command(char *);
static int try_access(const char *);
 
/* work-around for access() */
static int try_access(const char *f)
{
    int fd;
 
    fd = open(f, O_RDONLY);
    if (fd > -1) {
        close(fd);
        return 0;
    } else
        return -1;
}
 
/* Returns the full path of "cmd" if cmd is found, else just hand back
 * cmd as it was presented */
static char *find_command(char *cmd)
{
    char *path_tok;
    char *path[PATH_MAX];
    int n = 0, i = 0;
    size_t x = strlen(cmd) + 2;
 
    found = (char *)malloc(PATH_MAX);
 
    /* The user has specified a full or relative path, just give it back. */
    if (-1 != try_access(cmd)) {
        return (char *) cmd;
    }
 
    path_tok = strdup(PATH);
 
    /* Extract the PATH env to a path[] array */
    path[n] = strtok(path_tok, PATH_DELIM);
    while (NULL != path[n]) {
        if ((strlen(path[n]) + x ) > PATH_MAX) {
            cli_error(CL_ENOTSUP,
                "Segment %d of path is too large, search ends at segment %d",
                n, n-1);
            break;
        }
        path[++n] = strtok(NULL, PATH_DELIM);
    }
 
    /* We now have n places to look for the command */
    for (i=0; path[i]; i++) {
        memset(found, 0, sizeof(found));
        snprintf(found, PATH_MAX, "%s/%s", path[i], cmd);
        if (-1 != try_access(found)) {
            free(path_tok);
            return (char *) found;
        }
    }
 
    /* We didn't find it, just give it back as-is. */
    free(path_tok);
    return (char *) cmd;
}
 
unsigned int try_exec(char *cmd, char **argv)
{
    task_id_t tid;
    char *tmp;
 
    tmp = strdup(find_command(cmd));
    free(found);
 
    tid = task_spawn((const char *)tmp, argv);
    free(tmp);
 
    if (tid == 0) {
        cli_error(CL_EEXEC, "Cannot spawn `%s'.", cmd);
        return 1;
    } else {
        return 0;
    }
}
 

Rev 4341	Rev 4346
1	/* Copyright (c) 2008, Tim Post <tinkertim@gmail.com>	1	/* Copyright (c) 2008, Tim Post <tinkertim@gmail.com>
2	* All rights reserved.	2	* All rights reserved.
3	*	3	*
4	* Redistribution and use in source and binary forms, with or without	4	* Redistribution and use in source and binary forms, with or without
5	* modification, are permitted provided that the following conditions are met:	5	* modification, are permitted provided that the following conditions are met:
6	*	6	*
7	* Redistributions of source code must retain the above copyright notice, this	7	* Redistributions of source code must retain the above copyright notice, this
8	* list of conditions and the following disclaimer.	8	* list of conditions and the following disclaimer.
9	*	9	*
10	* Redistributions in binary form must reproduce the above copyright notice,	10	* Redistributions in binary form must reproduce the above copyright notice,
11	* this list of conditions and the following disclaimer in the documentation	11	* this list of conditions and the following disclaimer in the documentation
12	* and/or other materials provided with the distribution.	12	* and/or other materials provided with the distribution.
13	*	13	*
14	* Neither the name of the original program's authors nor the names of its	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	15	* contributors may be used to endorse or promote products derived from this
16	* software without specific prior written permission.	16	* software without specific prior written permission.
17	*	17	*
18	* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"	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	19	* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE	20	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21	* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE	21	* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
22	* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR	22	* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
23	* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF	23	* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
24	* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS	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	25	* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
26	* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)	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	27	* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
28	* POSSIBILITY OF SUCH DAMAGE.	28	* POSSIBILITY OF SUCH DAMAGE.
29	*/	29	*/
30		30
31	/* The VERY basics of execute in place support. These are buggy, leaky	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!!	32	* and not nearly done. Only here for beta testing!! You were warned!!
33	* TODO:	33	* TODO:
34	* Hash command lookups to save time	34	* Hash command lookups to save time
35	* Create a running pointer to *path and advance/rewind it as we go /	35	* Create a running pointer to *path and advance/rewind it as we go /
36		36
37	#include <stdio.h>	37	#include <stdio.h>
38	#include <stdlib.h>	38	#include <stdlib.h>
39	#include <unistd.h>	39	#include <unistd.h>
40	#include <string.h>	40	#include <string.h>
41	#include <fcntl.h>	41	#include <fcntl.h>
42		42
43	#include "config.h"	43	#include "config.h"
44	#include "util.h"	44	#include "util.h"
45	#include "exec.h"	45	#include "exec.h"
46	#include "errors.h"	46	#include "errors.h"
47		47
48	/* FIXME: Just have find_command() return an allocated string */	48	/* FIXME: Just have find_command() return an allocated string */
49	static char *found;	49	static char *found;
50		50
51	static char find_command(char );	51	static char find_command(char );
52	static int try_access(const char *);	52	static int try_access(const char *);
53		53
54	/* work-around for access() */	54	/* work-around for access() */
55	static int try_access(const char *f)	55	static int try_access(const char *f)
56	{	56	{
57	int fd;	57	int fd;
58		58
59	fd = open(f, O_RDONLY);	59	fd = open(f, O_RDONLY);
60	if (fd > -1) {	60	if (fd > -1) {
61	close(fd);	61	close(fd);
62	return 0;	62	return 0;
63	} else	63	} else
64	return -1;	64	return -1;
65	}	65	}
66		66
67	/* Returns the full path of "cmd" if cmd is found, else just hand back	67	/* Returns the full path of "cmd" if cmd is found, else just hand back
68	* cmd as it was presented */	68	* cmd as it was presented */
69	static char find_command(char cmd)	69	static char find_command(char cmd)
70	{	70	{
71	char *path_tok;	71	char *path_tok;
72	char *path[PATH_MAX];	72	char *path[PATH_MAX];
73	int n = 0, i = 0;	73	int n = 0, i = 0;
74	size_t x = strlen(cmd) + 2;	74	size_t x = strlen(cmd) + 2;
75		75
76	found = (char *)malloc(PATH_MAX);	76	found = (char *)malloc(PATH_MAX);
77		77
78	/* The user has specified a full or relative path, just give it back. */	78	/* The user has specified a full or relative path, just give it back. */
79	if (-1 != try_access(cmd)) {	79	if (-1 != try_access(cmd)) {
80	return (char *) cmd;	80	return (char *) cmd;
81	}	81	}
82		82
83	path_tok = strdup(PATH);	83	path_tok = strdup(PATH);
84		84
85	/* Extract the PATH env to a path[] array */	85	/* Extract the PATH env to a path[] array */
86	path[n] = strtok(path_tok, PATH_DELIM);	86	path[n] = strtok(path_tok, PATH_DELIM);
87	while (NULL != path[n]) {	87	while (NULL != path[n]) {
88	if ((strlen(path[n]) + x ) > PATH_MAX) {	88	if ((strlen(path[n]) + x ) > PATH_MAX) {
89	cli_error(CL_ENOTSUP,	89	cli_error(CL_ENOTSUP,
90	"Segment %d of path is too large, search ends at segment %d",	90	"Segment %d of path is too large, search ends at segment %d",
91	n, n-1);	91	n, n-1);
92	break;	92	break;
93	}	93	}
94	path[++n] = strtok(NULL, PATH_DELIM);	94	path[++n] = strtok(NULL, PATH_DELIM);
95	}	95	}
96		96
97	/* We now have n places to look for the command */	97	/* We now have n places to look for the command */
98	for (i=0; path[i]; i++) {	98	for (i=0; path[i]; i++) {
99	memset(found, 0, sizeof(found));	99	memset(found, 0, sizeof(found));
100	snprintf(found, PATH_MAX, "%s/%s", path[i], cmd);	100	snprintf(found, PATH_MAX, "%s/%s", path[i], cmd);
101	if (-1 != try_access(found)) {	101	if (-1 != try_access(found)) {
102	free(path_tok);	102	free(path_tok);
103	return (char *) found;	103	return (char *) found;
104	}	104	}
105	}	105	}
106		106
107	/* We didn't find it, just give it back as-is. */	107	/* We didn't find it, just give it back as-is. */
108	free(path_tok);	108	free(path_tok);
109	return (char *) cmd;	109	return (char *) cmd;
110	}	110	}
111		111
112	unsigned int try_exec(char cmd, char *argv)	112	unsigned int try_exec(char cmd, char *argv)
113	{	113	{
114	task_id_t tid;	114	task_id_t tid;
115	char *tmp;	115	char *tmp;
116		116
117	tmp = strdup(find_command(cmd));	117	tmp = strdup(find_command(cmd));
118	free(found);	118	free(found);
119		119
120	tid = task_spawn((const char *)tmp, argv);	120	tid = task_spawn((const char *)tmp, argv);
121	free(tmp);	121	free(tmp);
122		122
123	if (tid == 0) {	123	if (tid == 0) {
124	cli_error(CL_EEXEC, "Can not spawn %s", cmd);	124	cli_error(CL_EEXEC, "Cannot spawn `%s'.", cmd);
125	return 1;	125	return 1;
126	} else {	126	} else {
127	return 0;	127	return 0;
128	}	128	}
129	}	129	}
130		130

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(root)/branches/dynload/uspace/app/bdsh/exec.c – Rev 4341 → 4346