WebSVN – HelenOS – Diff – /branches/dd/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>
 
#ifndef HELENOS
#include <linux/limits.h>
#include <sys/errno.h>
#include <sys/wait.h>
#endif
 
#include "config.h"
#include "util.h"
#include "exec.h"
#include "errors.h"
 
/* Easiest way to handle a shared + allocated string, a structure with
 * one member is sort of silly :) */
char *found;
 
/* work-around for access() */
unsigned 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 */
char *find_command(char *cmd)
{
    char *path_orig, *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. */
#ifdef HELENOS
    if (-1 != try_access(cmd))
#else
    if (-1 != access(cmd, F_OK))
#endif
    {
        return (char *) cmd;
    }
 
#ifdef HELENOS
    path_orig = PATH;
#else
    path_orig = getenv("PATH");
    if (NULL == path_orig)
        path_orig = PATH;
#endif
 
    path_tok = cli_strdup(path_orig);
 
    /* Extract the PATH env to a path[] array */
    path[n] = cli_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] = cli_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);
#ifdef HELENOS
        if (-1 != try_access(found))
#else
        if (-1 != access(found, F_OK))
#endif
        {
 
            free(path_tok);
            return (char *) found;
        }
    }
 
    /* We didn't find it, just give it back as-is. Could be an alias
     * set in the parent shell */
    free(path_tok);
    return (char *) cmd;
}
 
#ifdef HELENOS
task_id_t try_exec(char *cmd, char **argv)
{
    task_id_t tid;
    char *tmp;
 
    tmp = cli_strdup(find_command(cmd));
    free(found);
 
    tid = task_spawn((const char *)tmp, (const char **)argv);
    free(tmp);
 
    if (tid == 0)
        /* HelenOS does not set errno, so all we can do is report
         * a task ID of 0 as a generic failure. */
        cli_error(CL_EEXEC, "Can not spawn %s", cmd);
 
    return tid;
}
 
#else
int try_exec(char *cmd, char **argv)
{
    char *tmp;
    pid_t pid;
    int status;
 
    /* Copy the result of allocated 'found' */
    tmp = cli_strdup(find_command(cmd));
    /* free the pointer, no longer needed */
    free(found);
 
    if (-1 == (access(tmp, F_OK))) {
        cli_error(CL_EFAIL,
            "%s : No such external, modular or builtin command", tmp);
        free(tmp);
        return CL_EFAIL;
    }
 
    /* Create a child to run the program */
    pid = fork();
    if (pid == 0) {
        execv(tmp, argv);
        exit(errno);
    } else if (pid > 0) {
        /* Block until we get a PID (and result) */
        wait(&status);
        status = status / 256;
    } else {
        /* Could not fork, ulimit or out of memory */
        cli_error(CL_ENOMEM, "Could not fork");
        free(tmp);
        return CL_ENOMEM;
    }
 
    free(tmp);
 
 
 
 
 
 
    /* Decode any errors from execv() (these explain themselves) */
    switch (status) {
    case ENOTDIR:
        cli_error(CL_EFAIL, "%s : No such file or directory", tmp);
        status = CL_EFAIL;
        break;
    case EISDIR:
        cli_error(CL_EFAIL, "%s : Command is a directory", tmp);
        status = CL_EFAIL;
        break;
    case EACCES:
        cli_error(CL_EPERM, "%s :", tmp);
        status = CL_EFAIL;
        break;
    case ENOMEM:
        cli_error(CL_ENOMEM, "%s :", tmp);
        status = CL_EFAIL;
        break;
    case ENAMETOOLONG:
        cli_error(CL_EFAIL, "Argument list too long");
        status = CL_EFAIL;
        break;
    case EFAULT:
        cli_error(CL_EFAIL, "Invalid argument pointer\n(please report "
            "this to %s)", PACKAGE_BUGREPORT);
        status = CL_EFAIL;
        break;
    }
 
    return status;
}
 
#endif /* HELENOS */
 

Rev 3265	Rev 3287
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	#ifndef HELENOS	43	#ifndef HELENOS
44	#include <linux/limits.h>	44	#include <linux/limits.h>
45	#include <sys/errno.h>	45	#include <sys/errno.h>
46	#include <sys/wait.h>	46	#include <sys/wait.h>
47	#endif	47	#endif
48		48
49	#include "config.h"	49	#include "config.h"
50	#include "util.h"	50	#include "util.h"
51	#include "exec.h"	51	#include "exec.h"
52	#include "errors.h"	52	#include "errors.h"
53		53
54	/* Easiest way to handle a shared + allocated string, a structure with	54	/* Easiest way to handle a shared + allocated string, a structure with
55	* one member is sort of silly :) */	55	* one member is sort of silly :) */
56	char *found;	56	char *found;
57		57
58	/* work-around for access() */	58	/* work-around for access() */
59	unsigned int try_access(const char *f)	59	unsigned int try_access(const char *f)
60	{	60	{
61	int fd;	61	int fd;
62		62
63	fd = open(f, O_RDONLY);	63	fd = open(f, O_RDONLY);
64	if (fd > 0) {	64	if (fd > -1) {
65	close(fd);	65	close(fd);
66	return 1;	-
67	} else	-
68	return 0;	66	return 0;
-		67	} else
-		68	return -1;
69	}	69	}
70		70
71	/* Returns the full path of "cmd" if cmd is found, else just hand back	71	/* Returns the full path of "cmd" if cmd is found, else just hand back
72	* cmd as it was presented */	72	* cmd as it was presented */
73	char find_command(char cmd)	73	char find_command(char cmd)
74	{	74	{
75	char path_orig, path_tok;	75	char path_orig, path_tok;
76	char *path[PATH_MAX];	76	char *path[PATH_MAX];
77	int rc, n = 0, i = 0;	77	int n = 0, i = 0;
78	size_t x = strlen(cmd) + 2;	78	size_t x = strlen(cmd) + 2;
79		79
80	found = (char *)malloc(PATH_MAX);	80	found = (char *)malloc(PATH_MAX);
81		81
82	/* The user has specified the full path, just give it back. Don't test it,	82	/* The user has specified a full or relative path, just give it back. */
-		83	#ifdef HELENOS
83	* they seem to know what they're doing. */	84	if (-1 != try_access(cmd))
-		85	#else
84	if (cmd[0] == '/' \|\| cmd [0] == '.')	86	if (-1 != access(cmd, F_OK))
-		87	#endif
-		88	{
85	return (char *)cmd;	89	return (char *) cmd;
-		90	}
86		91
87	#ifdef HELENOS	92	#ifdef HELENOS
88	path_orig = PATH;	93	path_orig = PATH;
89	#else	94	#else
90	path_orig = getenv("PATH");	95	path_orig = getenv("PATH");
91	if (NULL == path_orig)	96	if (NULL == path_orig)
92	path_orig = PATH;	97	path_orig = PATH;
93	#endif	98	#endif
94		99
95	path_tok = cli_strdup(path_orig);	100	path_tok = cli_strdup(path_orig);
96		101
97	/* Extract the PATH env to a path[] array */	102	/* Extract the PATH env to a path[] array */
98	path[n] = cli_strtok(path_tok, PATH_DELIM);	103	path[n] = cli_strtok(path_tok, PATH_DELIM);
99	while (NULL != path[n]) {	104	while (NULL != path[n]) {
100	if ((strlen(path[n]) + x ) > PATH_MAX) {	105	if ((strlen(path[n]) + x ) > PATH_MAX) {
101	cli_error(CL_ENOTSUP,	106	cli_error(CL_ENOTSUP,
102	"Segment %d of path is too large, search ends at segment %d",	107	"Segment %d of path is too large, search ends at segment %d",
103	n, n-1);	108	n, n-1);
104	break;	109	break;
105	}	110	}
106	path[++n] = cli_strtok(NULL, PATH_DELIM);	111	path[++n] = cli_strtok(NULL, PATH_DELIM);
107	}	112	}
108		113
109	/* We now have n places to look for the command */	114	/* We now have n places to look for the command */
110	for (i=0; path[i]; i++) {	115	for (i=0; path[i]; i++) {
111	memset(found, 0, sizeof(found));	116	memset(found, 0, sizeof(found));
112	snprintf(found, PATH_MAX, "%s/%s", path[i], cmd);	117	snprintf(found, PATH_MAX, "%s/%s", path[i], cmd);
113	#ifdef HELENOS	118	#ifdef HELENOS
114	rc = try_access(found);	119	if (-1 != try_access(found))
115	#else	120	#else
116	rc = access(found, F_OK);	121	if (-1 != access(found, F_OK))
117	#endif	122	#endif
118	if (rc >= 0) {	123	{
119	/* We found it */	-
120	free(path_tok);	124	free(path_tok);
121	return (char *) found;	125	return (char *) found;
122	}	126	}
123	}	127	}
124		128
125	/* We didn't find it, just give it back as-is. Could be an alias	129	/* We didn't find it, just give it back as-is. Could be an alias
126	* set in the parent shell */	130	* set in the parent shell */
127	free(path_tok);	131	free(path_tok);
128	return (char *) cmd;	132	return (char *) cmd;
129	}	133	}
130		134
131	#ifdef HELENOS	135	#ifdef HELENOS
132	task_id_t try_exec(char cmd, char *argv)	136	task_id_t try_exec(char cmd, char *argv)
133	{	137	{
134	task_id_t tid;	138	task_id_t tid;
135	char *tmp;	139	char *tmp;
136		140
137	tmp = cli_strdup(find_command(cmd));	141	tmp = cli_strdup(find_command(cmd));
138	free(found);	142	free(found);
139		143
140	tid = task_spawn((const char )tmp, (const char *)argv);	144	tid = task_spawn((const char )tmp, (const char *)argv);
141	free(tmp);	145	free(tmp);
142		146
143	if (tid == 0)	147	if (tid == 0)
144	/* HelenOS does not set errno, so all we can do is report	148	/* HelenOS does not set errno, so all we can do is report
145	* a task ID of 0 as a generic failure. */	149	* a task ID of 0 as a generic failure. */
146	cli_error(CL_EEXEC, "Can not spawn %s", cmd);	150	cli_error(CL_EEXEC, "Can not spawn %s", cmd);
147		151
148	return tid;	152	return tid;
149	}	153	}
150		154
151	#else	155	#else
152	int try_exec(char cmd, char *argv)	156	int try_exec(char cmd, char *argv)
153	{	157	{
154	char *tmp;	158	char *tmp;
155	pid_t pid;	159	pid_t pid;
156	int status;	160	int status;
157		161
158	/* Copy the result of allocated 'found' */	162	/* Copy the result of allocated 'found' */
159	tmp = cli_strdup(find_command(cmd));	163	tmp = cli_strdup(find_command(cmd));
160	/* free the pointer, no longer needed */	164	/* free the pointer, no longer needed */
161	free(found);	165	free(found);
162		166
163	if (-1 == (access(tmp, F_OK))) {	167	if (-1 == (access(tmp, F_OK))) {
164	cli_error(CL_EFAIL,	168	cli_error(CL_EFAIL,
165	"%s : No such external, modular or builtin command", tmp);	169	"%s : No such external, modular or builtin command", tmp);
166	free(tmp);	170	free(tmp);
167	return CL_EFAIL;	171	return CL_EFAIL;
168	}	172	}
169		173
170	/* Create a child to run the program */	174	/* Create a child to run the program */
171	pid = fork();	175	pid = fork();
172	if (pid == 0) {	176	if (pid == 0) {
173	execv(tmp, argv);	177	execv(tmp, argv);
174	exit(errno);	178	exit(errno);
175	} else if (pid > 0) {	179	} else if (pid > 0) {
176	/* Block until we get a PID (and result) */	180	/* Block until we get a PID (and result) */
177	wait(&status);	181	wait(&status);
178	status = status / 256;	182	status = status / 256;
179	} else {	183	} else {
180	/* Could not fork, ulimit or out of memory */	184	/* Could not fork, ulimit or out of memory */
181	cli_error(CL_ENOMEM, "Could not fork");	185	cli_error(CL_ENOMEM, "Could not fork");
182	free(tmp);	186	free(tmp);
183	return CL_ENOMEM;	187	return CL_ENOMEM;
184	}	188	}
185		189
186	free(tmp);	190	free(tmp);
187		191
188	/* No need to go any further if status == 0 */	-
189	/*	-
190	if (status == 0)	-
191	return status;	-
192	*/	-
193	/* Decode any errors from execv() (these explain themselves) */	192	/* Decode any errors from execv() (these explain themselves) */
194	switch (status) {	193	switch (status) {
195	case ENOTDIR:	194	case ENOTDIR:
196	cli_error(CL_EFAIL, "%s : No such file or directory", tmp);	195	cli_error(CL_EFAIL, "%s : No such file or directory", tmp);
197	status = CL_EFAIL;	196	status = CL_EFAIL;
198	break;	197	break;
199	case EISDIR:	198	case EISDIR:
200	cli_error(CL_EFAIL, "%s : Command is a directory", tmp);	199	cli_error(CL_EFAIL, "%s : Command is a directory", tmp);
201	status = CL_EFAIL;	200	status = CL_EFAIL;
202	break;	201	break;
203	case EACCES:	202	case EACCES:
204	cli_error(CL_EPERM, "%s :", tmp);	203	cli_error(CL_EPERM, "%s :", tmp);
205	status = CL_EFAIL;	204	status = CL_EFAIL;
206	break;	205	break;
207	case ENOMEM:	206	case ENOMEM:
208	cli_error(CL_ENOMEM, "%s :", tmp);	207	cli_error(CL_ENOMEM, "%s :", tmp);
209	status = CL_EFAIL;	208	status = CL_EFAIL;
210	break;	209	break;
211	case ENAMETOOLONG:	210	case ENAMETOOLONG:
212	cli_error(CL_EFAIL, "Argument list too long");	211	cli_error(CL_EFAIL, "Argument list too long");
213	status = CL_EFAIL;	212	status = CL_EFAIL;
214	break;	213	break;
215	case EFAULT:	214	case EFAULT:
216	cli_error(CL_EFAIL, "Invalid argument pointer\n(please report "	215	cli_error(CL_EFAIL, "Invalid argument pointer\n(please report "
217	"this to %s)", PACKAGE_BUGREPORT);	216	"this to %s)", PACKAGE_BUGREPORT);
218	status = CL_EFAIL;	217	status = CL_EFAIL;
219	break;	218	break;
220	}	219	}
221		220
222	return status;	221	return status;
223	}	222	}
224		223
225	#endif /* HELENOS */	224	#endif /* HELENOS */
226		225

Subversion Repositories HelenOS

(root)/branches/dd/uspace/app/bdsh/exec.c @ 4347 – Rev 3265 → 3287