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 * Free memory previous allocated with os_malloc()/os_realloc() 111 * 112 * This returns the memory to the OS. 113 * 114 * \param ptr Pointer to memory block to free 115 */ 116 void os_free(void *ptr); 117 118 /** 119 * Reallocate previously-allocated memory to increase/decrease space 120 * 121 * This works in a similar way to the C library realloc() function. If 122 * length is 0, then ptr is freed. Otherwise the space used by ptr is 123 * expanded or reduced depending on whether length is larger or smaller 124 * than before. 125 * 126 * If ptr is NULL, then this is similar to calling os_malloc(). 127 * 128 * This function may need to move the memory block to make room for any 129 * extra space, in which case the new pointer is returned. 130 * 131 * \param ptr Pointer to memory block to reallocate 132 * \param length New length for memory block 133 * \return pointer to new memory block, or NULL on failure or if length 134 * is 0. 135 */ 136 void *os_realloc(void *ptr, size_t length); 137 138 /** 139 * Access to the usleep function of the os 140 * 141 * \param usec Time to sleep in micro seconds 142 */ 143 void os_usleep(unsigned long usec); 144 145 /** 146 * Gets a monotonic increasing number of nano seconds from the OS 147 * 148 * \return A monotonic increasing time scaled in nano seconds 149 */ 150 uint64_t os_get_nsec(void); 151 152 /** 153 * Parse arguments and update sandbox state. 154 * 155 * @param state Sandbox state to update 156 * @param argc Argument count 157 * @param argv Argument vector 158 * @return 0 if ok, and program should continue; 159 * 1 if ok, but program should stop; 160 * -1 on error: program should terminate. 161 */ 162 int os_parse_args(struct sandbox_state *state, int argc, char *argv[]); 163 164 /* 165 * Types of directory entry that we support. See also os_dirent_typename in 166 * the C file. 167 */ 168 enum os_dirent_t { 169 OS_FILET_REG, /* Regular file */ 170 OS_FILET_LNK, /* Symbolic link */ 171 OS_FILET_DIR, /* Directory */ 172 OS_FILET_UNKNOWN, /* Something else */ 173 174 OS_FILET_COUNT, 175 }; 176 177 /** A directory entry node, containing information about a single dirent */ 178 struct os_dirent_node { 179 struct os_dirent_node *next; /* Pointer to next node, or NULL */ 180 ulong size; /* Size of file in bytes */ 181 enum os_dirent_t type; /* Type of entry */ 182 char name[0]; /* Name of entry */ 183 }; 184 185 /** 186 * Get a directionry listing 187 * 188 * This allocates and returns a linked list containing the directory listing. 189 * 190 * @param dirname Directory to examine 191 * @param headp Returns pointer to head of linked list, or NULL if none 192 * @return 0 if ok, -ve on error 193 */ 194 int os_dirent_ls(const char *dirname, struct os_dirent_node **headp); 195 196 /** 197 * Get the name of a directory entry type 198 * 199 * @param type Type to cehck 200 * @return string containing the name of that type, or "???" if none/invalid 201 */ 202 const char *os_dirent_get_typename(enum os_dirent_t type); 203 204 /** 205 * Get the size of a file 206 * 207 * @param fname Filename to check 208 * @return size of file, or -1 if an error ocurred 209 */ 210 ssize_t os_get_filesize(const char *fname); 211 212 /** 213 * Write a character to the controlling OS terminal 214 * 215 * This bypasses the U-Boot console support and writes directly to the OS 216 * stdout file descriptor. 217 * 218 * @param ch Character to write 219 */ 220 void os_putc(int ch); 221 222 /** 223 * Write a string to the controlling OS terminal 224 * 225 * This bypasses the U-Boot console support and writes directly to the OS 226 * stdout file descriptor. 227 * 228 * @param str String to write (note that \n is not appended) 229 */ 230 void os_puts(const char *str); 231 232 /** 233 * Write the sandbox RAM buffer to a existing file 234 * 235 * @param fname Filename to write memory to (simple binary format) 236 * @return 0 if OK, -ve on error 237 */ 238 int os_write_ram_buf(const char *fname); 239 240 /** 241 * Read the sandbox RAM buffer from an existing file 242 * 243 * @param fname Filename containing memory (simple binary format) 244 * @return 0 if OK, -ve on error 245 */ 246 int os_read_ram_buf(const char *fname); 247 248 #endif 249