xref: /openbmc/u-boot/include/os.h (revision 68fbc0e6)
1 /*
2  * Operating System Interface
3  *
4  * This provides access to useful OS routines for the sandbox architecture.
5  * They are kept in a separate file so we can include system headers.
6  *
7  * Copyright (c) 2011 The Chromium OS Authors.
8  * See file CREDITS for list of people who contributed to this
9  * project.
10  *
11  * This program is free software; you can redistribute it and/or
12  * modify it under the terms of the GNU General Public License as
13  * published by the Free Software Foundation; either version 2 of
14  * the License, or (at your option) any later version.
15  *
16  * This program is distributed in the hope that it will be useful,
17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
19  * GNU General Public License for more details.
20  *
21  * You should have received a copy of the GNU General Public License
22  * along with this program; if not, write to the Free Software
23  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
24  * MA 02111-1307 USA
25  */
26 
27 #ifndef __OS_H__
28 #define __OS_H__
29 
30 struct sandbox_state;
31 
32 /**
33  * Access to the OS read() system call
34  *
35  * \param fd	File descriptor as returned by os_open()
36  * \param buf	Buffer to place data
37  * \param count	Number of bytes to read
38  * \return number of bytes read, or -1 on error
39  */
40 ssize_t os_read(int fd, void *buf, size_t count);
41 
42 /**
43  * Access to the OS read() system call with non-blocking access
44  *
45  * \param fd	File descriptor as returned by os_open()
46  * \param buf	Buffer to place data
47  * \param count	Number of bytes to read
48  * \return number of bytes read, or -1 on error
49  */
50 ssize_t os_read_no_block(int fd, void *buf, size_t count);
51 
52 /**
53  * Access to the OS write() system call
54  *
55  * \param fd	File descriptor as returned by os_open()
56  * \param buf	Buffer containing data to write
57  * \param count	Number of bytes to write
58  * \return number of bytes written, or -1 on error
59  */
60 ssize_t os_write(int fd, const void *buf, size_t count);
61 
62 /**
63  * Access to the OS lseek() system call
64  *
65  * \param fd	File descriptor as returned by os_open()
66  * \param offset	File offset (based on whence)
67  * \param whence	Position offset is relative to (see below)
68  * \return new file offset
69  */
70 off_t os_lseek(int fd, off_t offset, int whence);
71 
72 /* Defines for "whence" in os_lseek() */
73 #define OS_SEEK_SET	0
74 #define OS_SEEK_CUR	1
75 #define OS_SEEK_END	2
76 
77 /**
78  * Access to the OS open() system call
79  *
80  * \param pathname	Pathname of file to open
81  * \param flags		Flags, like O_RDONLY, O_RDWR
82  * \return file descriptor, or -1 on error
83  */
84 int os_open(const char *pathname, int flags);
85 
86 #define OS_O_RDONLY	0
87 #define OS_O_WRONLY	1
88 #define OS_O_RDWR	2
89 #define OS_O_MASK	3	/* Mask for read/write flags */
90 #define OS_O_CREAT	0100
91 
92 /**
93  * Access to the OS close() system call
94  *
95  * \param fd	File descriptor to close
96  * \return 0 on success, -1 on error
97  */
98 int os_close(int fd);
99 
100 /**
101  * Access to the OS exit() system call
102  *
103  * This exits with the supplied return code, which should be 0 to indicate
104  * success.
105  *
106  * @param exit_code	exit code for U-Boot
107  */
108 void os_exit(int exit_code) __attribute__((noreturn));
109 
110 /**
111  * Put tty into raw mode to mimic serial console better
112  */
113 void os_tty_raw(int fd);
114 
115 /**
116  * Acquires some memory from the underlying os.
117  *
118  * \param length	Number of bytes to be allocated
119  * \return Pointer to length bytes or NULL on error
120  */
121 void *os_malloc(size_t length);
122 
123 /**
124  * Access to the usleep function of the os
125  *
126  * \param usec Time to sleep in micro seconds
127  */
128 void os_usleep(unsigned long usec);
129 
130 /**
131  * Gets a monotonic increasing number of nano seconds from the OS
132  *
133  * \return A monotonic increasing time scaled in nano seconds
134  */
135 u64 os_get_nsec(void);
136 
137 /**
138  * Parse arguments and update sandbox state.
139  *
140  * @param state		Sandbox state to update
141  * @param argc		Argument count
142  * @param argv		Argument vector
143  * @return 0 if ok, and program should continue;
144  *	1 if ok, but program should stop;
145  *	-1 on error: program should terminate.
146  */
147 int os_parse_args(struct sandbox_state *state, int argc, char *argv[]);
148 
149 /*
150  * Types of directory entry that we support. See also os_dirent_typename in
151  * the C file.
152  */
153 enum os_dirent_t {
154 	OS_FILET_REG,		/* Regular file */
155 	OS_FILET_LNK,		/* Symbolic link */
156 	OS_FILET_DIR,		/* Directory */
157 	OS_FILET_UNKNOWN,	/* Something else */
158 
159 	OS_FILET_COUNT,
160 };
161 
162 /** A directory entry node, containing information about a single dirent */
163 struct os_dirent_node {
164 	struct os_dirent_node *next;	/* Pointer to next node, or NULL */
165 	ulong size;			/* Size of file in bytes */
166 	enum os_dirent_t type;		/* Type of entry */
167 	char name[0];			/* Name of entry */
168 };
169 
170 /**
171  * Get a directionry listing
172  *
173  * This allocates and returns a linked list containing the directory listing.
174  *
175  * @param dirname	Directory to examine
176  * @param headp		Returns pointer to head of linked list, or NULL if none
177  * @return 0 if ok, -ve on error
178  */
179 int os_dirent_ls(const char *dirname, struct os_dirent_node **headp);
180 
181 /**
182  * Get the name of a directory entry type
183  *
184  * @param type		Type to cehck
185  * @return string containing the name of that type, or "???" if none/invalid
186  */
187 const char *os_dirent_get_typename(enum os_dirent_t type);
188 
189 /**
190  * Get the size of a file
191  *
192  * @param fname		Filename to check
193  * @return size of file, or -1 if an error ocurred
194  */
195 ssize_t os_get_filesize(const char *fname);
196 
197 #endif
198