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 unlink() system call 88 * 89 * \param pathname Path of file to delete 90 * \return 0 for success, other for error 91 */ 92 int os_unlink(const char *pathname); 93 94 /** 95 * Access to the OS exit() system call 96 * 97 * This exits with the supplied return code, which should be 0 to indicate 98 * success. 99 * 100 * @param exit_code exit code for U-Boot 101 */ 102 void os_exit(int exit_code) __attribute__((noreturn)); 103 104 /** 105 * Put tty into raw mode to mimic serial console better 106 * 107 * @param fd File descriptor of stdin (normally 0) 108 * @param allow_sigs Allow Ctrl-C, Ctrl-Z to generate signals rather than 109 * be handled by U-Boot 110 */ 111 void os_tty_raw(int fd, bool allow_sigs); 112 113 /** 114 * Acquires some memory from the underlying os. 115 * 116 * \param length Number of bytes to be allocated 117 * \return Pointer to length bytes or NULL on error 118 */ 119 void *os_malloc(size_t length); 120 121 /** 122 * Free memory previous allocated with os_malloc()/os_realloc() 123 * 124 * This returns the memory to the OS. 125 * 126 * \param ptr Pointer to memory block to free 127 */ 128 void os_free(void *ptr); 129 130 /** 131 * Reallocate previously-allocated memory to increase/decrease space 132 * 133 * This works in a similar way to the C library realloc() function. If 134 * length is 0, then ptr is freed. Otherwise the space used by ptr is 135 * expanded or reduced depending on whether length is larger or smaller 136 * than before. 137 * 138 * If ptr is NULL, then this is similar to calling os_malloc(). 139 * 140 * This function may need to move the memory block to make room for any 141 * extra space, in which case the new pointer is returned. 142 * 143 * \param ptr Pointer to memory block to reallocate 144 * \param length New length for memory block 145 * \return pointer to new memory block, or NULL on failure or if length 146 * is 0. 147 */ 148 void *os_realloc(void *ptr, size_t length); 149 150 /** 151 * Access to the usleep function of the os 152 * 153 * \param usec Time to sleep in micro seconds 154 */ 155 void os_usleep(unsigned long usec); 156 157 /** 158 * Gets a monotonic increasing number of nano seconds from the OS 159 * 160 * \return A monotonic increasing time scaled in nano seconds 161 */ 162 uint64_t os_get_nsec(void); 163 164 /** 165 * Parse arguments and update sandbox state. 166 * 167 * @param state Sandbox state to update 168 * @param argc Argument count 169 * @param argv Argument vector 170 * @return 0 if ok, and program should continue; 171 * 1 if ok, but program should stop; 172 * -1 on error: program should terminate. 173 */ 174 int os_parse_args(struct sandbox_state *state, int argc, char *argv[]); 175 176 /* 177 * Types of directory entry that we support. See also os_dirent_typename in 178 * the C file. 179 */ 180 enum os_dirent_t { 181 OS_FILET_REG, /* Regular file */ 182 OS_FILET_LNK, /* Symbolic link */ 183 OS_FILET_DIR, /* Directory */ 184 OS_FILET_UNKNOWN, /* Something else */ 185 186 OS_FILET_COUNT, 187 }; 188 189 /** A directory entry node, containing information about a single dirent */ 190 struct os_dirent_node { 191 struct os_dirent_node *next; /* Pointer to next node, or NULL */ 192 ulong size; /* Size of file in bytes */ 193 enum os_dirent_t type; /* Type of entry */ 194 char name[0]; /* Name of entry */ 195 }; 196 197 /** 198 * Get a directionry listing 199 * 200 * This allocates and returns a linked list containing the directory listing. 201 * 202 * @param dirname Directory to examine 203 * @param headp Returns pointer to head of linked list, or NULL if none 204 * @return 0 if ok, -ve on error 205 */ 206 int os_dirent_ls(const char *dirname, struct os_dirent_node **headp); 207 208 /** 209 * Get the name of a directory entry type 210 * 211 * @param type Type to cehck 212 * @return string containing the name of that type, or "???" if none/invalid 213 */ 214 const char *os_dirent_get_typename(enum os_dirent_t type); 215 216 /** 217 * Get the size of a file 218 * 219 * @param fname Filename to check 220 * @return size of file, or -1 if an error ocurred 221 */ 222 ssize_t os_get_filesize(const char *fname); 223 224 /** 225 * Write a character to the controlling OS terminal 226 * 227 * This bypasses the U-Boot console support and writes directly to the OS 228 * stdout file descriptor. 229 * 230 * @param ch Character to write 231 */ 232 void os_putc(int ch); 233 234 /** 235 * Write a string to the controlling OS terminal 236 * 237 * This bypasses the U-Boot console support and writes directly to the OS 238 * stdout file descriptor. 239 * 240 * @param str String to write (note that \n is not appended) 241 */ 242 void os_puts(const char *str); 243 244 /** 245 * Write the sandbox RAM buffer to a existing file 246 * 247 * @param fname Filename to write memory to (simple binary format) 248 * @return 0 if OK, -ve on error 249 */ 250 int os_write_ram_buf(const char *fname); 251 252 /** 253 * Read the sandbox RAM buffer from an existing file 254 * 255 * @param fname Filename containing memory (simple binary format) 256 * @return 0 if OK, -ve on error 257 */ 258 int os_read_ram_buf(const char *fname); 259 260 /** 261 * Jump to a new executable image 262 * 263 * This uses exec() to run a new executable image, after putting it in a 264 * temporary file. The same arguments and environment are passed to this 265 * new image, with the addition of: 266 * 267 * -j <filename> Specifies the filename the image was written to. The 268 * calling image may want to delete this at some point. 269 * -m <filename> Specifies the file containing the sandbox memory 270 * (ram_buf) from this image, so that the new image can 271 * have access to this. It also means that the original 272 * memory filename passed to U-Boot will be left intact. 273 * 274 * @param dest Buffer containing executable image 275 * @param size Size of buffer 276 */ 277 int os_jump_to_image(const void *dest, int size); 278 279 #endif 280