xref: /aosp_15_r20/external/e2fsprogs/lib/ss/help.c (revision 6a54128f25917bfc36a8a6e9d722c04a0b4641b6)
1 /*
2  * Copyright 1987, 1988 by MIT Student Information Processing Board
3  *
4  * Permission to use, copy, modify, and distribute this software and
5  * its documentation for any purpose is hereby granted, provided that
6  * the names of M.I.T. and the M.I.T. S.I.P.B. not be used in
7  * advertising or publicity pertaining to distribution of the software
8  * without specific, written prior permission.  M.I.T. and the
9  * M.I.T. S.I.P.B. make no representations about the suitability of
10  * this software for any purpose.  It is provided "as is" without
11  * express or implied warranty.
12  */
13 
14 #include "config.h"
15 #ifdef HAVE_UNISTD_H
16 #include <unistd.h>
17 #endif
18 #ifdef HAVE_STDLIB_H
19 #include <stdlib.h>
20 #endif
21 #ifdef HAVE_ERRNO_H
22 #include <errno.h>
23 #endif
24 #include <fcntl.h>
25 #include <sys/param.h>
26 #include <sys/types.h>
27 #include <sys/file.h>
28 #ifdef NEED_SYS_FCNTL_H
29 /* just for O_* */
30 #include <sys/fcntl.h>
31 #endif
32 #ifdef HAVE_SYS_WAIT_H
33 #include <sys/wait.h>
34 #endif
35 #include "ss_internal.h"
36 
ss_help(int argc,char const * const * argv,int sci_idx,pointer info_ptr)37 void ss_help(int argc, char const * const *argv, int sci_idx, pointer info_ptr)
38 {
39     char *buffer;
40     char const *request_name;
41     int code;
42     int fd, child;
43     register int idx;
44     register ss_data *info;
45 
46     request_name = ss_current_request(sci_idx, &code);
47     if (code != 0) {
48 	ss_perror(sci_idx, code, "");
49 	return;		/* no ss_abort_line, if invalid invocation */
50     }
51     if (argc == 1) {
52 	ss_list_requests(argc, argv, sci_idx, info_ptr);
53 	return;
54     }
55     else if (argc != 2) {
56 	/* should do something better than this */
57 	buffer = malloc(80+2*strlen(request_name));
58 	if (!buffer) {
59 		ss_perror(sci_idx, 0,
60 			  "couldn't allocate memory to print usage message");
61 		return;
62 	}
63 	sprintf(buffer, "usage:\n\t%s [topic|command]\nor\t%s\n",
64 		request_name, request_name);
65 	ss_perror(sci_idx, 0, buffer);
66 	free(buffer);
67 	return;
68     }
69     info = ss_info(sci_idx);
70     if (info->info_dirs == (char **)NULL) {
71 	ss_perror(sci_idx, SS_ET_NO_INFO_DIR, (char *)NULL);
72 	return;
73     }
74     if (info->info_dirs[0] == (char *)NULL) {
75 	ss_perror(sci_idx, SS_ET_NO_INFO_DIR, (char *)NULL);
76 	return;
77     }
78     for (fd = -1, idx = 0; info->info_dirs[idx] != (char *)NULL; idx++) {
79         buffer = malloc(strlen (info->info_dirs[idx]) + 1 +
80 			strlen (argv[1]) + 6);
81 	if (!buffer) {
82 	    ss_perror(sci_idx, 0,
83 		      "couldn't allocate memory for help filename");
84 	    return;
85 	}
86 	(void) strcpy(buffer, info->info_dirs[idx]);
87 	(void) strcat(buffer, "/");
88 	(void) strcat(buffer, argv[1]);
89 	(void) strcat(buffer, ".info");
90 	fd = open(buffer, O_RDONLY);
91 	free(buffer);
92 	if (fd >= 0)
93 	    break;
94     }
95     if (fd < 0) {
96 #define MSG "No info found for "
97 	char *buf = malloc(strlen (MSG) + strlen (argv[1]) + 1);
98 	if (!buf) {
99 		ss_perror(sci_idx, 0,
100 			  "couldn't allocate memory to print error message");
101 		return;
102 	}
103 	strcpy(buf, MSG);
104 	strcat(buf, argv[1]);
105 	ss_perror(sci_idx, 0, buf);
106 	free(buf);
107 	return;
108     }
109     switch (child = fork()) {
110     case -1:
111 	ss_perror(sci_idx, errno, "Can't fork for pager");
112 	(void) close(fd);
113 	return;
114     case 0:
115 	(void) dup2(fd, 0); /* put file on stdin */
116 	ss_page_stdin();
117     default:
118 	(void) close(fd); /* what can we do if it fails? */
119 	while (wait(NULL) != child) {
120 	    /* do nothing if wrong pid */
121 	};
122     }
123 }
124 
125 #ifndef HAVE_DIRENT_H
126 #include <sys/dir.h>
127 #else
128 #include <dirent.h>
129 #endif
130 
ss_add_info_dir(int sci_idx,char * info_dir,int * code_ptr)131 void ss_add_info_dir(int sci_idx, char *info_dir, int *code_ptr)
132 {
133     register ss_data *info;
134     DIR *d;
135     int n_dirs;
136     register char **dirs;
137 
138     info = ss_info(sci_idx);
139     if (info_dir == NULL || *info_dir == '\0') {
140 	*code_ptr = SS_ET_NO_INFO_DIR;
141 	return;
142     }
143     if ((d = opendir(info_dir)) == (DIR *)NULL) {
144 	*code_ptr = errno;
145 	return;
146     }
147     closedir(d);
148     dirs = info->info_dirs;
149     for (n_dirs = 0; dirs[n_dirs] != (char *)NULL; n_dirs++)
150 	;		/* get number of non-NULL dir entries */
151     dirs = (char **)realloc((char *)dirs,
152 			    (unsigned)(n_dirs + 2)*sizeof(char *));
153     if (dirs == (char **)NULL) {
154 	*code_ptr = ENOMEM;
155 	return;
156     }
157     info->info_dirs = dirs;
158     dirs[n_dirs + 1] = (char *)NULL;
159     dirs[n_dirs] = malloc((unsigned)strlen(info_dir)+1);
160     if (dirs[n_dirs] == (char *)NULL) {
161         *code_ptr = ENOMEM;
162         return;
163     }
164     strcpy(dirs[n_dirs], info_dir);
165     *code_ptr = 0;
166 }
167 
ss_delete_info_dir(int sci_idx,char * info_dir,int * code_ptr)168 void ss_delete_info_dir(int sci_idx, char *info_dir, int *code_ptr)
169 {
170     register char **i_d;
171     register char **info_dirs;
172 
173     info_dirs = ss_info(sci_idx)->info_dirs;
174     for (i_d = info_dirs; *i_d; i_d++) {
175 	if (!strcmp(*i_d, info_dir)) {
176 	    while (*i_d) {
177 		*i_d = *(i_d+1);
178 		i_d++;
179 	    }
180 	    *code_ptr = 0;
181 	    return;
182 	}
183     }
184     *code_ptr = SS_ET_NO_INFO_DIR;
185 }
186