xref: /openbmc/u-boot/include/os.h (revision 0ae76531)
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  * SPDX-License-Identifier:	GPL-2.0+
9  */
10 
11 #ifndef __OS_H__
12 #define __OS_H__
13 
14 #include <linux/types.h>
15 
16 struct sandbox_state;
17 
18 /**
19  * Access to the OS read() system call
20  *
21  * \param fd	File descriptor as returned by os_open()
22  * \param buf	Buffer to place data
23  * \param count	Number of bytes to read
24  * \return number of bytes read, or -1 on error
25  */
26 ssize_t os_read(int fd, void *buf, size_t count);
27 
28 /**
29  * Access to the OS read() system call with non-blocking access
30  *
31  * \param fd	File descriptor as returned by os_open()
32  * \param buf	Buffer to place data
33  * \param count	Number of bytes to read
34  * \return number of bytes read, or -1 on error
35  */
36 ssize_t os_read_no_block(int fd, void *buf, size_t count);
37 
38 /**
39  * Access to the OS write() system call
40  *
41  * \param fd	File descriptor as returned by os_open()
42  * \param buf	Buffer containing data to write
43  * \param count	Number of bytes to write
44  * \return number of bytes written, or -1 on error
45  */
46 ssize_t os_write(int fd, const void *buf, size_t count);
47 
48 /**
49  * Access to the OS lseek() system call
50  *
51  * \param fd	File descriptor as returned by os_open()
52  * \param offset	File offset (based on whence)
53  * \param whence	Position offset is relative to (see below)
54  * \return new file offset
55  */
56 off_t os_lseek(int fd, off_t offset, int whence);
57 
58 /* Defines for "whence" in os_lseek() */
59 #define OS_SEEK_SET	0
60 #define OS_SEEK_CUR	1
61 #define OS_SEEK_END	2
62 
63 /**
64  * Access to the OS open() system call
65  *
66  * \param pathname	Pathname of file to open
67  * \param flags		Flags, like O_RDONLY, O_RDWR
68  * \return file descriptor, or -1 on error
69  */
70 int os_open(const char *pathname, int flags);
71 
72 #define OS_O_RDONLY	0
73 #define OS_O_WRONLY	1
74 #define OS_O_RDWR	2
75 #define OS_O_MASK	3	/* Mask for read/write flags */
76 #define OS_O_CREAT	0100
77 
78 /**
79  * Access to the OS close() system call
80  *
81  * \param fd	File descriptor to close
82  * \return 0 on success, -1 on error
83  */
84 int os_close(int fd);
85 
86 /**
87  * Access to the OS exit() system call
88  *
89  * This exits with the supplied return code, which should be 0 to indicate
90  * success.
91  *
92  * @param exit_code	exit code for U-Boot
93  */
94 void os_exit(int exit_code) __attribute__((noreturn));
95 
96 /**
97  * Put tty into raw mode to mimic serial console better
98  */
99 void os_tty_raw(int fd);
100 
101 /**
102  * Acquires some memory from the underlying os.
103  *
104  * \param length	Number of bytes to be allocated
105  * \return Pointer to length bytes or NULL on error
106  */
107 void *os_malloc(size_t length);
108 
109 /**
110  * Access to the usleep function of the os
111  *
112  * \param usec Time to sleep in micro seconds
113  */
114 void os_usleep(unsigned long usec);
115 
116 /**
117  * Gets a monotonic increasing number of nano seconds from the OS
118  *
119  * \return A monotonic increasing time scaled in nano seconds
120  */
121 uint64_t os_get_nsec(void);
122 
123 /**
124  * Parse arguments and update sandbox state.
125  *
126  * @param state		Sandbox state to update
127  * @param argc		Argument count
128  * @param argv		Argument vector
129  * @return 0 if ok, and program should continue;
130  *	1 if ok, but program should stop;
131  *	-1 on error: program should terminate.
132  */
133 int os_parse_args(struct sandbox_state *state, int argc, char *argv[]);
134 
135 /*
136  * Types of directory entry that we support. See also os_dirent_typename in
137  * the C file.
138  */
139 enum os_dirent_t {
140 	OS_FILET_REG,		/* Regular file */
141 	OS_FILET_LNK,		/* Symbolic link */
142 	OS_FILET_DIR,		/* Directory */
143 	OS_FILET_UNKNOWN,	/* Something else */
144 
145 	OS_FILET_COUNT,
146 };
147 
148 /** A directory entry node, containing information about a single dirent */
149 struct os_dirent_node {
150 	struct os_dirent_node *next;	/* Pointer to next node, or NULL */
151 	ulong size;			/* Size of file in bytes */
152 	enum os_dirent_t type;		/* Type of entry */
153 	char name[0];			/* Name of entry */
154 };
155 
156 /**
157  * Get a directionry listing
158  *
159  * This allocates and returns a linked list containing the directory listing.
160  *
161  * @param dirname	Directory to examine
162  * @param headp		Returns pointer to head of linked list, or NULL if none
163  * @return 0 if ok, -ve on error
164  */
165 int os_dirent_ls(const char *dirname, struct os_dirent_node **headp);
166 
167 /**
168  * Get the name of a directory entry type
169  *
170  * @param type		Type to cehck
171  * @return string containing the name of that type, or "???" if none/invalid
172  */
173 const char *os_dirent_get_typename(enum os_dirent_t type);
174 
175 /**
176  * Get the size of a file
177  *
178  * @param fname		Filename to check
179  * @return size of file, or -1 if an error ocurred
180  */
181 ssize_t os_get_filesize(const char *fname);
182 
183 #endif
184