| 1 | #ifndef PUTTY_PUTTY_H |
| 2 | #define PUTTY_PUTTY_H |
| 3 | |
| 4 | #include <stddef.h> /* for wchar_t */ |
| 5 | |
| 6 | /* |
| 7 | * Global variables. Most modules declare these `extern', but |
| 8 | * window.c will do `#define PUTTY_DO_GLOBALS' before including this |
| 9 | * module, and so will get them properly defined. |
| 10 | */ |
| 11 | #ifndef GLOBAL |
| 12 | #ifdef PUTTY_DO_GLOBALS |
| 13 | #define GLOBAL |
| 14 | #else |
| 15 | #define GLOBAL extern |
| 16 | #endif |
| 17 | #endif |
| 18 | |
| 19 | #ifndef DONE_TYPEDEFS |
| 20 | #define DONE_TYPEDEFS |
| 21 | typedef struct config_tag Config; |
| 22 | typedef struct backend_tag Backend; |
| 23 | typedef struct terminal_tag Terminal; |
| 24 | #endif |
| 25 | |
| 26 | #include "puttyps.h" |
| 27 | #include "network.h" |
| 28 | #include "misc.h" |
| 29 | |
| 30 | /* Three attribute types: |
| 31 | * The ATTRs (normal attributes) are stored with the characters in |
| 32 | * the main display arrays |
| 33 | * |
| 34 | * The TATTRs (temporary attributes) are generated on the fly, they |
| 35 | * can overlap with characters but not with normal attributes. |
| 36 | * |
| 37 | * The LATTRs (line attributes) are an entirely disjoint space of |
| 38 | * flags. |
| 39 | * |
| 40 | * The DATTRs (display attributes) are internal to terminal.c (but |
| 41 | * defined here because their values have to match the others |
| 42 | * here); they reuse the TATTR_* space but are always masked off |
| 43 | * before sending to the front end. |
| 44 | * |
| 45 | * ATTR_INVALID is an illegal colour combination. |
| 46 | */ |
| 47 | |
| 48 | #define TATTR_ACTCURS 0x40000000UL /* active cursor (block) */ |
| 49 | #define TATTR_PASCURS 0x20000000UL /* passive cursor (box) */ |
| 50 | #define TATTR_RIGHTCURS 0x10000000UL /* cursor-on-RHS */ |
| 51 | #define TATTR_COMBINING 0x80000000UL /* combining characters */ |
| 52 | |
| 53 | #define DATTR_STARTRUN 0x80000000UL /* start of redraw run */ |
| 54 | |
| 55 | #define TDATTR_MASK 0xF0000000UL |
| 56 | #define TATTR_MASK (TDATTR_MASK) |
| 57 | #define DATTR_MASK (TDATTR_MASK) |
| 58 | |
| 59 | #define LATTR_NORM 0x00000000UL |
| 60 | #define LATTR_WIDE 0x00000001UL |
| 61 | #define LATTR_TOP 0x00000002UL |
| 62 | #define LATTR_BOT 0x00000003UL |
| 63 | #define LATTR_MODE 0x00000003UL |
| 64 | #define LATTR_WRAPPED 0x00000010UL |
| 65 | #define LATTR_WRAPPED2 0x00000020UL |
| 66 | |
| 67 | #define ATTR_INVALID 0x03FFFFU |
| 68 | |
| 69 | /* Like Linux use the F000 page for direct to font. */ |
| 70 | #define CSET_OEMCP 0x0000F000UL /* OEM Codepage DTF */ |
| 71 | #define CSET_ACP 0x0000F100UL /* Ansi Codepage DTF */ |
| 72 | |
| 73 | /* These are internal use overlapping with the UTF-16 surrogates */ |
| 74 | #define CSET_ASCII 0x0000D800UL /* normal ASCII charset ESC ( B */ |
| 75 | #define CSET_LINEDRW 0x0000D900UL /* line drawing charset ESC ( 0 */ |
| 76 | #define CSET_SCOACS 0x0000DA00UL /* SCO Alternate charset */ |
| 77 | #define CSET_GBCHR 0x0000DB00UL /* UK variant charset ESC ( A */ |
| 78 | #define CSET_MASK 0xFFFFFF00UL /* Character set mask */ |
| 79 | |
| 80 | #define DIRECT_CHAR(c) ((c&0xFFFFFC00)==0xD800) |
| 81 | #define DIRECT_FONT(c) ((c&0xFFFFFE00)==0xF000) |
| 82 | |
| 83 | #define UCSERR (CSET_LINEDRW|'a') /* UCS Format error character. */ |
| 84 | /* |
| 85 | * UCSWIDE is a special value used in the terminal data to signify |
| 86 | * the character cell containing the right-hand half of a CJK wide |
| 87 | * character. We use 0xDFFF because it's part of the surrogate |
| 88 | * range and hence won't be used for anything else (it's impossible |
| 89 | * to input it via UTF-8 because our UTF-8 decoder correctly |
| 90 | * rejects surrogates). |
| 91 | */ |
| 92 | #define UCSWIDE 0xDFFF |
| 93 | |
| 94 | #define ATTR_NARROW 0x800000U |
| 95 | #define ATTR_WIDE 0x400000U |
| 96 | #define ATTR_BOLD 0x040000U |
| 97 | #define ATTR_UNDER 0x080000U |
| 98 | #define ATTR_REVERSE 0x100000U |
| 99 | #define ATTR_BLINK 0x200000U |
| 100 | #define ATTR_FGMASK 0x0001FFU |
| 101 | #define ATTR_BGMASK 0x03FE00U |
| 102 | #define ATTR_COLOURS 0x03FFFFU |
| 103 | #define ATTR_FGSHIFT 0 |
| 104 | #define ATTR_BGSHIFT 9 |
| 105 | |
| 106 | /* |
| 107 | * The definitive list of colour numbers stored in terminal |
| 108 | * attribute words is kept here. It is: |
| 109 | * |
| 110 | * - 0-7 are ANSI colours (KRGYBMCW). |
| 111 | * - 8-15 are the bold versions of those colours. |
| 112 | * - 16-255 are the remains of the xterm 256-colour mode (a |
| 113 | * 216-colour cube with R at most significant and B at least, |
| 114 | * followed by a uniform series of grey shades running between |
| 115 | * black and white but not including either on grounds of |
| 116 | * redundancy). |
| 117 | * - 256 is default foreground |
| 118 | * - 257 is default bold foreground |
| 119 | * - 258 is default background |
| 120 | * - 259 is default bold background |
| 121 | * - 260 is cursor foreground |
| 122 | * - 261 is cursor background |
| 123 | */ |
| 124 | |
| 125 | #define ATTR_DEFFG (256 << ATTR_FGSHIFT) |
| 126 | #define ATTR_DEFBG (258 << ATTR_BGSHIFT) |
| 127 | #define ATTR_DEFAULT (ATTR_DEFFG | ATTR_DEFBG) |
| 128 | |
| 129 | struct sesslist { |
| 130 | int nsessions; |
| 131 | char **sessions; |
| 132 | char *buffer; /* so memory can be freed later */ |
| 133 | }; |
| 134 | |
| 135 | struct unicode_data { |
| 136 | char **uni_tbl; |
| 137 | int dbcs_screenfont; |
| 138 | int font_codepage; |
| 139 | int line_codepage; |
| 140 | wchar_t unitab_scoacs[256]; |
| 141 | wchar_t unitab_line[256]; |
| 142 | wchar_t unitab_font[256]; |
| 143 | wchar_t unitab_xterm[256]; |
| 144 | wchar_t unitab_oemcp[256]; |
| 145 | unsigned char unitab_ctrl[256]; |
| 146 | }; |
| 147 | |
| 148 | #define LGXF_OVR 1 /* existing logfile overwrite */ |
| 149 | #define LGXF_APN 0 /* existing logfile append */ |
| 150 | #define LGXF_ASK -1 /* existing logfile ask */ |
| 151 | #define LGTYP_NONE 0 /* logmode: no logging */ |
| 152 | #define LGTYP_ASCII 1 /* logmode: pure ascii */ |
| 153 | #define LGTYP_DEBUG 2 /* logmode: all chars of traffic */ |
| 154 | #define LGTYP_PACKETS 3 /* logmode: SSH data packets */ |
| 155 | |
| 156 | typedef enum { |
| 157 | /* Actual special commands. Originally Telnet, but some codes have |
| 158 | * been re-used for similar specials in other protocols. */ |
| 159 | TS_AYT, TS_BRK, TS_SYNCH, TS_EC, TS_EL, TS_GA, TS_NOP, TS_ABORT, |
| 160 | TS_AO, TS_IP, TS_SUSP, TS_EOR, TS_EOF, TS_LECHO, TS_RECHO, TS_PING, |
| 161 | TS_EOL, |
| 162 | /* Special command for SSH. */ |
| 163 | TS_REKEY, |
| 164 | /* POSIX-style signals. (not Telnet) */ |
| 165 | TS_SIGABRT, TS_SIGALRM, TS_SIGFPE, TS_SIGHUP, TS_SIGILL, |
| 166 | TS_SIGINT, TS_SIGKILL, TS_SIGPIPE, TS_SIGQUIT, TS_SIGSEGV, |
| 167 | TS_SIGTERM, TS_SIGUSR1, TS_SIGUSR2, |
| 168 | /* Pseudo-specials used for constructing the specials menu. */ |
| 169 | TS_SEP, /* Separator */ |
| 170 | TS_SUBMENU, /* Start a new submenu with specified name */ |
| 171 | TS_EXITMENU /* Exit current submenu or end of specials */ |
| 172 | } Telnet_Special; |
| 173 | |
| 174 | struct telnet_special { |
| 175 | const char *name; |
| 176 | int code; |
| 177 | }; |
| 178 | |
| 179 | typedef enum { |
| 180 | MBT_NOTHING, |
| 181 | MBT_LEFT, MBT_MIDDLE, MBT_RIGHT, /* `raw' button designations */ |
| 182 | MBT_SELECT, MBT_EXTEND, MBT_PASTE, /* `cooked' button designations */ |
| 183 | MBT_WHEEL_UP, MBT_WHEEL_DOWN /* mouse wheel */ |
| 184 | } Mouse_Button; |
| 185 | |
| 186 | typedef enum { |
| 187 | MA_NOTHING, MA_CLICK, MA_2CLK, MA_3CLK, MA_DRAG, MA_RELEASE |
| 188 | } Mouse_Action; |
| 189 | |
| 190 | /* Keyboard modifiers -- keys the user is actually holding down */ |
| 191 | |
| 192 | #define PKM_SHIFT 0x01 |
| 193 | #define PKM_CONTROL 0x02 |
| 194 | #define PKM_META 0x04 |
| 195 | #define PKM_ALT 0x08 |
| 196 | |
| 197 | /* Keyboard flags that aren't really modifiers */ |
| 198 | #define PKF_CAPSLOCK 0x10 |
| 199 | #define PKF_NUMLOCK 0x20 |
| 200 | #define PKF_REPEAT 0x40 |
| 201 | |
| 202 | /* Stand-alone keysyms for function keys */ |
| 203 | |
| 204 | typedef enum { |
| 205 | PK_NULL, /* No symbol for this key */ |
| 206 | /* Main keypad keys */ |
| 207 | PK_ESCAPE, PK_TAB, PK_BACKSPACE, PK_RETURN, PK_COMPOSE, |
| 208 | /* Editing keys */ |
| 209 | PK_HOME, PK_INSERT, PK_DELETE, PK_END, PK_PAGEUP, PK_PAGEDOWN, |
| 210 | /* Cursor keys */ |
| 211 | PK_UP, PK_DOWN, PK_RIGHT, PK_LEFT, PK_REST, |
| 212 | /* Numeric keypad */ /* Real one looks like: */ |
| 213 | PK_PF1, PK_PF2, PK_PF3, PK_PF4, /* PF1 PF2 PF3 PF4 */ |
| 214 | PK_KPCOMMA, PK_KPMINUS, PK_KPDECIMAL, /* 7 8 9 - */ |
| 215 | PK_KP0, PK_KP1, PK_KP2, PK_KP3, PK_KP4, /* 4 5 6 , */ |
| 216 | PK_KP5, PK_KP6, PK_KP7, PK_KP8, PK_KP9, /* 1 2 3 en- */ |
| 217 | PK_KPBIGPLUS, PK_KPENTER, /* 0 . ter */ |
| 218 | /* Top row */ |
| 219 | PK_F1, PK_F2, PK_F3, PK_F4, PK_F5, |
| 220 | PK_F6, PK_F7, PK_F8, PK_F9, PK_F10, |
| 221 | PK_F11, PK_F12, PK_F13, PK_F14, PK_F15, |
| 222 | PK_F16, PK_F17, PK_F18, PK_F19, PK_F20, |
| 223 | PK_PAUSE |
| 224 | } Key_Sym; |
| 225 | |
| 226 | #define PK_ISEDITING(k) ((k) >= PK_HOME && (k) <= PK_PAGEDOWN) |
| 227 | #define PK_ISCURSOR(k) ((k) >= PK_UP && (k) <= PK_REST) |
| 228 | #define PK_ISKEYPAD(k) ((k) >= PK_PF1 && (k) <= PK_KPENTER) |
| 229 | #define PK_ISFKEY(k) ((k) >= PK_F1 && (k) <= PK_F20) |
| 230 | |
| 231 | enum { |
| 232 | VT_XWINDOWS, VT_OEMANSI, VT_OEMONLY, VT_POORMAN, VT_UNICODE |
| 233 | }; |
| 234 | |
| 235 | enum { |
| 236 | /* |
| 237 | * SSH-2 key exchange algorithms |
| 238 | */ |
| 239 | KEX_WARN, |
| 240 | KEX_DHGROUP1, |
| 241 | KEX_DHGROUP14, |
| 242 | KEX_DHGEX, |
| 243 | KEX_MAX |
| 244 | }; |
| 245 | |
| 246 | enum { |
| 247 | /* |
| 248 | * SSH ciphers (both SSH1 and SSH2) |
| 249 | */ |
| 250 | CIPHER_WARN, /* pseudo 'cipher' */ |
| 251 | CIPHER_3DES, |
| 252 | CIPHER_BLOWFISH, |
| 253 | CIPHER_AES, /* (SSH 2 only) */ |
| 254 | CIPHER_DES, |
| 255 | CIPHER_MAX /* no. ciphers (inc warn) */ |
| 256 | }; |
| 257 | |
| 258 | enum { |
| 259 | /* |
| 260 | * Several different bits of the PuTTY configuration seem to be |
| 261 | * three-way settings whose values are `always yes', `always |
| 262 | * no', and `decide by some more complex automated means'. This |
| 263 | * is true of line discipline options (local echo and line |
| 264 | * editing), proxy DNS, Close On Exit, and SSH server bug |
| 265 | * workarounds. Accordingly I supply a single enum here to deal |
| 266 | * with them all. |
| 267 | */ |
| 268 | FORCE_ON, FORCE_OFF, AUTO |
| 269 | }; |
| 270 | |
| 271 | enum { |
| 272 | /* |
| 273 | * Proxy types. |
| 274 | */ |
| 275 | PROXY_NONE, PROXY_SOCKS4, PROXY_SOCKS5, |
| 276 | PROXY_HTTP, PROXY_TELNET, PROXY_CMD |
| 277 | }; |
| 278 | |
| 279 | enum { |
| 280 | /* |
| 281 | * Line discipline options which the backend might try to control. |
| 282 | */ |
| 283 | LD_EDIT, /* local line editing */ |
| 284 | LD_ECHO /* local echo */ |
| 285 | }; |
| 286 | |
| 287 | enum { |
| 288 | /* Protocol back ends. (cfg.protocol) */ |
| 289 | PROT_RAW, PROT_TELNET, PROT_RLOGIN, PROT_SSH |
| 290 | }; |
| 291 | |
| 292 | enum { |
| 293 | /* Bell settings (cfg.beep) */ |
| 294 | BELL_DISABLED, BELL_DEFAULT, BELL_VISUAL, BELL_WAVEFILE, BELL_PCSPEAKER |
| 295 | }; |
| 296 | |
| 297 | enum { |
| 298 | /* Taskbar flashing indication on bell (cfg.beep_ind) */ |
| 299 | B_IND_DISABLED, B_IND_FLASH, B_IND_STEADY |
| 300 | }; |
| 301 | |
| 302 | enum { |
| 303 | /* Resize actions (cfg.resize_action) */ |
| 304 | RESIZE_TERM, RESIZE_DISABLED, RESIZE_FONT, RESIZE_EITHER |
| 305 | }; |
| 306 | |
| 307 | enum { |
| 308 | /* Function key types (cfg.funky_type) */ |
| 309 | FUNKY_TILDE, |
| 310 | FUNKY_LINUX, |
| 311 | FUNKY_XTERM, |
| 312 | FUNKY_VT400, |
| 313 | FUNKY_VT100P, |
| 314 | FUNKY_SCO |
| 315 | }; |
| 316 | |
| 317 | enum { |
| 318 | /* |
| 319 | * Network address types. Used for specifying choice of IPv4/v6 |
| 320 | * in config; also used in proxy.c to indicate whether a given |
| 321 | * host name has already been resolved or will be resolved at |
| 322 | * the proxy end. |
| 323 | */ |
| 324 | ADDRTYPE_UNSPEC, ADDRTYPE_IPV4, ADDRTYPE_IPV6, ADDRTYPE_NAME |
| 325 | }; |
| 326 | |
| 327 | struct backend_tag { |
| 328 | const char *(*init) (void *frontend_handle, void **backend_handle, |
| 329 | Config *cfg, |
| 330 | char *host, int port, char **realhost, int nodelay, |
| 331 | int keepalive); |
| 332 | void (*free) (void *handle); |
| 333 | /* back->reconfig() passes in a replacement configuration. */ |
| 334 | void (*reconfig) (void *handle, Config *cfg); |
| 335 | /* back->send() returns the current amount of buffered data. */ |
| 336 | int (*send) (void *handle, char *buf, int len); |
| 337 | /* back->sendbuffer() does the same thing but without attempting a send */ |
| 338 | int (*sendbuffer) (void *handle); |
| 339 | void (*size) (void *handle, int width, int height); |
| 340 | void (*special) (void *handle, Telnet_Special code); |
| 341 | const struct telnet_special *(*get_specials) (void *handle); |
| 342 | Socket(*socket) (void *handle); |
| 343 | int (*exitcode) (void *handle); |
| 344 | int (*sendok) (void *handle); |
| 345 | int (*ldisc) (void *handle, int); |
| 346 | void (*provide_ldisc) (void *handle, void *ldisc); |
| 347 | void (*provide_logctx) (void *handle, void *logctx); |
| 348 | /* |
| 349 | * back->unthrottle() tells the back end that the front end |
| 350 | * buffer is clearing. |
| 351 | */ |
| 352 | void (*unthrottle) (void *handle, int); |
| 353 | int (*cfg_info) (void *handle); |
| 354 | int default_port; |
| 355 | }; |
| 356 | |
| 357 | extern struct backend_list { |
| 358 | int protocol; |
| 359 | char *name; |
| 360 | Backend *backend; |
| 361 | } backends[]; |
| 362 | |
| 363 | /* |
| 364 | * Suggested default protocol provided by the backend link module. |
| 365 | * The application is free to ignore this. |
| 366 | */ |
| 367 | extern const int be_default_protocol; |
| 368 | |
| 369 | /* |
| 370 | * Name of this particular application, for use in the config box |
| 371 | * and other pieces of text. |
| 372 | */ |
| 373 | extern const char *const appname; |
| 374 | |
| 375 | /* |
| 376 | * IMPORTANT POLICY POINT: everything in this structure which wants |
| 377 | * to be treated like an integer must be an actual, honest-to- |
| 378 | * goodness `int'. No enum-typed variables. This is because parts |
| 379 | * of the code will want to pass around `int *' pointers to them |
| 380 | * and we can't run the risk of porting to some system on which the |
| 381 | * enum comes out as a different size from int. |
| 382 | */ |
| 383 | struct config_tag { |
| 384 | /* Basic options */ |
| 385 | char host[512]; |
| 386 | int port; |
| 387 | int protocol; |
| 388 | int addressfamily; |
| 389 | int close_on_exit; |
| 390 | int warn_on_close; |
| 391 | int ping_interval; /* in seconds */ |
| 392 | int tcp_nodelay; |
| 393 | int tcp_keepalives; |
| 394 | /* Proxy options */ |
| 395 | char proxy_exclude_list[512]; |
| 396 | int proxy_dns; |
| 397 | int even_proxy_localhost; |
| 398 | int proxy_type; |
| 399 | char proxy_host[512]; |
| 400 | int proxy_port; |
| 401 | char proxy_username[128]; |
| 402 | char proxy_password[128]; |
| 403 | char proxy_telnet_command[512]; |
| 404 | /* SSH options */ |
| 405 | char remote_cmd[512]; |
| 406 | char remote_cmd2[512]; /* fallback if the first fails |
| 407 | * (used internally for scp) */ |
| 408 | char *remote_cmd_ptr; /* might point to a larger command |
| 409 | * but never for loading/saving */ |
| 410 | char *remote_cmd_ptr2; /* might point to a larger command |
| 411 | * but never for loading/saving */ |
| 412 | int nopty; |
| 413 | int compression; |
| 414 | int ssh_kexlist[KEX_MAX]; |
| 415 | int ssh_rekey_time; /* in minutes */ |
| 416 | char ssh_rekey_data[16]; |
| 417 | int agentfwd; |
| 418 | int change_username; /* allow username switching in SSH2 */ |
| 419 | int ssh_cipherlist[CIPHER_MAX]; |
| 420 | Filename keyfile; |
| 421 | int sshprot; /* use v1 or v2 when both available */ |
| 422 | int ssh2_des_cbc; /* "des-cbc" nonstandard SSH2 cipher */ |
| 423 | int try_tis_auth; |
| 424 | int try_ki_auth; |
| 425 | int ssh_subsys; /* run a subsystem rather than a command */ |
| 426 | int ssh_subsys2; /* fallback to go with remote_cmd2 */ |
| 427 | int ssh_no_shell; /* avoid running a shell */ |
| 428 | /* Telnet options */ |
| 429 | char termtype[32]; |
| 430 | char termspeed[32]; |
| 431 | char environmt[1024]; /* VAR\tvalue\0VAR\tvalue\0\0 */ |
| 432 | char username[100]; |
| 433 | char localusername[100]; |
| 434 | int rfc_environ; |
| 435 | int passive_telnet; |
| 436 | /* Keyboard options */ |
| 437 | int bksp_is_delete; |
| 438 | int rxvt_homeend; |
| 439 | int funky_type; |
| 440 | int no_applic_c; /* totally disable app cursor keys */ |
| 441 | int no_applic_k; /* totally disable app keypad */ |
| 442 | int no_mouse_rep; /* totally disable mouse reporting */ |
| 443 | int no_remote_resize; /* disable remote resizing */ |
| 444 | int no_alt_screen; /* disable alternate screen */ |
| 445 | int no_remote_wintitle; /* disable remote retitling */ |
| 446 | int no_dbackspace; /* disable destructive backspace */ |
| 447 | int no_remote_charset; /* disable remote charset config */ |
| 448 | int no_remote_qtitle; /* disable remote win title query */ |
| 449 | int app_cursor; |
| 450 | int app_keypad; |
| 451 | int nethack_keypad; |
| 452 | int telnet_keyboard; |
| 453 | int telnet_newline; |
| 454 | int alt_f4; /* is it special? */ |
| 455 | int alt_space; /* is it special? */ |
| 456 | int alt_only; /* is it special? */ |
| 457 | int localecho; |
| 458 | int localedit; |
| 459 | int alwaysontop; |
| 460 | int fullscreenonaltenter; |
| 461 | int scroll_on_key; |
| 462 | int scroll_on_disp; |
| 463 | int erase_to_scrollback; |
| 464 | int compose_key; |
| 465 | int ctrlaltkeys; |
| 466 | char wintitle[256]; /* initial window title */ |
| 467 | /* Terminal options */ |
| 468 | int savelines; |
| 469 | int dec_om; |
| 470 | int wrap_mode; |
| 471 | int lfhascr; |
| 472 | int cursor_type; /* 0=block 1=underline 2=vertical */ |
| 473 | int blink_cur; |
| 474 | int beep; |
| 475 | int beep_ind; |
| 476 | int bellovl; /* bell overload protection active? */ |
| 477 | int bellovl_n; /* number of bells to cause overload */ |
| 478 | int bellovl_t; /* time interval for overload (seconds) */ |
| 479 | int bellovl_s; /* period of silence to re-enable bell (s) */ |
| 480 | Filename bell_wavefile; |
| 481 | int scrollbar; |
| 482 | int scrollbar_in_fullscreen; |
| 483 | int resize_action; |
| 484 | int bce; |
| 485 | int blinktext; |
| 486 | int win_name_always; |
| 487 | int width, height; |
| 488 | FontSpec font; |
| 489 | Filename logfilename; |
| 490 | int logtype; |
| 491 | int logxfovr; |
| 492 | int logflush; |
| 493 | int logomitpass; |
| 494 | int logomitdata; |
| 495 | int hide_mouseptr; |
| 496 | int sunken_edge; |
| 497 | int window_border; |
| 498 | char answerback[256]; |
| 499 | char printer[128]; |
| 500 | int arabicshaping; |
| 501 | int bidi; |
| 502 | /* Colour options */ |
| 503 | int ansi_colour; |
| 504 | int xterm_256_colour; |
| 505 | int system_colour; |
| 506 | int try_palette; |
| 507 | int bold_colour; |
| 508 | unsigned char colours[22][3]; |
| 509 | /* Selection options */ |
| 510 | int mouse_is_xterm; |
| 511 | int rect_select; |
| 512 | int rawcnp; |
| 513 | int rtf_paste; |
| 514 | int mouse_override; |
| 515 | short wordness[256]; |
| 516 | /* translations */ |
| 517 | int vtmode; |
| 518 | char line_codepage[128]; |
| 519 | int utf8_override; |
| 520 | int xlat_capslockcyr; |
| 521 | /* X11 forwarding */ |
| 522 | int x11_forward; |
| 523 | char x11_display[128]; |
| 524 | int x11_auth; |
| 525 | /* port forwarding */ |
| 526 | int lport_acceptall; /* accept conns from hosts other than localhost */ |
| 527 | int rport_acceptall; /* same for remote forwarded ports (SSH2 only) */ |
| 528 | /* |
| 529 | * The port forwarding string contains a number of |
| 530 | * NUL-terminated substrings, terminated in turn by an empty |
| 531 | * string (i.e. a second NUL immediately after the previous |
| 532 | * one). Each string can be of one of the following forms: |
| 533 | * |
| 534 | * [LR]localport\thost:port |
| 535 | * [LR]localaddr:localport\thost:port |
| 536 | * Dlocalport |
| 537 | * Dlocaladdr:localport |
| 538 | */ |
| 539 | char portfwd[1024]; |
| 540 | /* SSH bug compatibility modes */ |
| 541 | int sshbug_ignore1, sshbug_plainpw1, sshbug_rsa1, |
| 542 | sshbug_hmac2, sshbug_derivekey2, sshbug_rsapad2, |
| 543 | sshbug_pksessid2, sshbug_rekey2; |
| 544 | /* Options for pterm. Should split out into platform-dependent part. */ |
| 545 | int stamp_utmp; |
| 546 | int login_shell; |
| 547 | int scrollbar_on_left; |
| 548 | int shadowbold; |
| 549 | FontSpec boldfont; |
| 550 | FontSpec widefont; |
| 551 | FontSpec wideboldfont; |
| 552 | int shadowboldoffset; |
| 553 | }; |
| 554 | |
| 555 | /* |
| 556 | * Some global flags denoting the type of application. |
| 557 | * |
| 558 | * FLAG_VERBOSE is set when the user requests verbose details. |
| 559 | * |
| 560 | * FLAG_STDERR is set in command-line applications (which have a |
| 561 | * functioning stderr that it makes sense to write to) and not in |
| 562 | * GUI applications (which don't). |
| 563 | * |
| 564 | * FLAG_INTERACTIVE is set when a full interactive shell session is |
| 565 | * being run, _either_ because no remote command has been provided |
| 566 | * _or_ because the application is GUI and can't run non- |
| 567 | * interactively. |
| 568 | * |
| 569 | * These flags describe the type of _application_ - they wouldn't |
| 570 | * vary between individual sessions - and so it's OK to have this |
| 571 | * variable be GLOBAL. |
| 572 | * |
| 573 | * Note that additional flags may be defined in platform-specific |
| 574 | * headers. It's probably best if those ones start from 0x1000, to |
| 575 | * avoid collision. |
| 576 | */ |
| 577 | #define FLAG_VERBOSE 0x0001 |
| 578 | #define FLAG_STDERR 0x0002 |
| 579 | #define FLAG_INTERACTIVE 0x0004 |
| 580 | GLOBAL int flags; |
| 581 | |
| 582 | /* |
| 583 | * Likewise, these two variables are set up when the application |
| 584 | * initialises, and inform all default-settings accesses after |
| 585 | * that. |
| 586 | */ |
| 587 | GLOBAL int default_protocol; |
| 588 | GLOBAL int default_port; |
| 589 | |
| 590 | /* |
| 591 | * This is set TRUE by cmdline.c iff a session is loaded with "-load". |
| 592 | */ |
| 593 | GLOBAL int loaded_session; |
| 594 | |
| 595 | struct RSAKey; /* be a little careful of scope */ |
| 596 | |
| 597 | /* |
| 598 | * Exports from window.c. |
| 599 | */ |
| 600 | void request_resize(void *frontend, int, int); |
| 601 | void do_text(Context, int, int, wchar_t *, int, unsigned long, int); |
| 602 | void do_cursor(Context, int, int, wchar_t *, int, unsigned long, int); |
| 603 | int char_width(Context ctx, int uc); |
| 604 | #ifdef OPTIMISE_SCROLL |
| 605 | void do_scroll(Context, int, int, int); |
| 606 | #endif |
| 607 | void set_title(void *frontend, char *); |
| 608 | void set_icon(void *frontend, char *); |
| 609 | void set_sbar(void *frontend, int, int, int); |
| 610 | Context get_ctx(void *frontend); |
| 611 | void free_ctx(Context); |
| 612 | void palette_set(void *frontend, int, int, int, int); |
| 613 | void palette_reset(void *frontend); |
| 614 | void write_aclip(void *frontend, char *, int, int); |
| 615 | void write_clip(void *frontend, wchar_t *, int, int); |
| 616 | void get_clip(void *frontend, wchar_t **, int *); |
| 617 | void optimised_move(void *frontend, int, int, int); |
| 618 | void set_raw_mouse_mode(void *frontend, int); |
| 619 | void connection_fatal(void *frontend, char *, ...); |
| 620 | void fatalbox(char *, ...); |
| 621 | void modalfatalbox(char *, ...); |
| 622 | #ifdef macintosh |
| 623 | #pragma noreturn(fatalbox) |
| 624 | #pragma noreturn(modalfatalbox) |
| 625 | #endif |
| 626 | void beep(void *frontend, int); |
| 627 | void begin_session(void *frontend); |
| 628 | void sys_cursor(void *frontend, int x, int y); |
| 629 | void request_paste(void *frontend); |
| 630 | void frontend_keypress(void *frontend); |
| 631 | void ldisc_update(void *frontend, int echo, int edit); |
| 632 | /* It's the backend's responsibility to invoke this at the start of a |
| 633 | * connection, if necessary; it can also invoke it later if the set of |
| 634 | * special commands changes. It does not need to invoke it at session |
| 635 | * shutdown. */ |
| 636 | void update_specials_menu(void *frontend); |
| 637 | int from_backend(void *frontend, int is_stderr, const char *data, int len); |
| 638 | void notify_remote_exit(void *frontend); |
| 639 | #define OPTIMISE_IS_SCROLL 1 |
| 640 | |
| 641 | void set_iconic(void *frontend, int iconic); |
| 642 | void move_window(void *frontend, int x, int y); |
| 643 | void set_zorder(void *frontend, int top); |
| 644 | void refresh_window(void *frontend); |
| 645 | void set_zoomed(void *frontend, int zoomed); |
| 646 | int is_iconic(void *frontend); |
| 647 | void get_window_pos(void *frontend, int *x, int *y); |
| 648 | void get_window_pixels(void *frontend, int *x, int *y); |
| 649 | char *get_window_title(void *frontend, int icon); |
| 650 | /* Hint from backend to frontend about time-consuming operations. |
| 651 | * Initial state is assumed to be BUSY_NOT. */ |
| 652 | enum { |
| 653 | BUSY_NOT, /* Not busy, all user interaction OK */ |
| 654 | BUSY_WAITING, /* Waiting for something; local event loops still running |
| 655 | so some local interaction (e.g. menus) OK, but network |
| 656 | stuff is suspended */ |
| 657 | BUSY_CPU /* Locally busy (e.g. crypto); user interaction suspended */ |
| 658 | }; |
| 659 | void set_busy_status(void *frontend, int status); |
| 660 | |
| 661 | void cleanup_exit(int); |
| 662 | |
| 663 | /* |
| 664 | * Exports from noise.c. |
| 665 | */ |
| 666 | void noise_get_heavy(void (*func) (void *, int)); |
| 667 | void noise_get_light(void (*func) (void *, int)); |
| 668 | void noise_regular(void); |
| 669 | void noise_ultralight(unsigned long data); |
| 670 | void random_save_seed(void); |
| 671 | void random_destroy_seed(void); |
| 672 | |
| 673 | /* |
| 674 | * Exports from settings.c. |
| 675 | */ |
| 676 | char *save_settings(char *section, int do_host, Config * cfg); |
| 677 | void save_open_settings(void *sesskey, int do_host, Config *cfg); |
| 678 | void load_settings(char *section, int do_host, Config * cfg); |
| 679 | void load_open_settings(void *sesskey, int do_host, Config *cfg); |
| 680 | void get_sesslist(struct sesslist *, int allocate); |
| 681 | void do_defaults(char *, Config *); |
| 682 | void registry_cleanup(void); |
| 683 | |
| 684 | /* |
| 685 | * Functions used by settings.c to provide platform-specific |
| 686 | * default settings. |
| 687 | * |
| 688 | * (The integer one is expected to return `def' if it has no clear |
| 689 | * opinion of its own. This is because there's no integer value |
| 690 | * which I can reliably set aside to indicate `nil'. The string |
| 691 | * function is perfectly all right returning NULL, of course. The |
| 692 | * Filename and FontSpec functions are _not allowed_ to fail to |
| 693 | * return, since these defaults _must_ be per-platform.) |
| 694 | */ |
| 695 | char *platform_default_s(const char *name); |
| 696 | int platform_default_i(const char *name, int def); |
| 697 | Filename platform_default_filename(const char *name); |
| 698 | FontSpec platform_default_fontspec(const char *name); |
| 699 | |
| 700 | /* |
| 701 | * Exports from terminal.c. |
| 702 | */ |
| 703 | |
| 704 | Terminal *term_init(Config *, struct unicode_data *, void *); |
| 705 | void term_free(Terminal *); |
| 706 | void term_size(Terminal *, int, int, int); |
| 707 | void term_paint(Terminal *, Context, int, int, int, int, int); |
| 708 | void term_scroll(Terminal *, int, int); |
| 709 | void term_pwron(Terminal *); |
| 710 | void term_clrsb(Terminal *); |
| 711 | void term_mouse(Terminal *, Mouse_Button, Mouse_Button, Mouse_Action, |
| 712 | int,int,int,int,int); |
| 713 | void term_key(Terminal *, Key_Sym, wchar_t *, size_t, unsigned int, |
| 714 | unsigned int); |
| 715 | void term_deselect(Terminal *); |
| 716 | void term_update(Terminal *); |
| 717 | void term_invalidate(Terminal *); |
| 718 | void term_blink(Terminal *, int set_cursor); |
| 719 | void term_do_paste(Terminal *); |
| 720 | int term_paste_pending(Terminal *); |
| 721 | void term_paste(Terminal *); |
| 722 | void term_nopaste(Terminal *); |
| 723 | int term_ldisc(Terminal *, int option); |
| 724 | void term_copyall(Terminal *); |
| 725 | void term_reconfig(Terminal *, Config *); |
| 726 | void term_seen_key_event(Terminal *); |
| 727 | int term_data(Terminal *, int is_stderr, const char *data, int len); |
| 728 | void term_provide_resize_fn(Terminal *term, |
| 729 | void (*resize_fn)(void *, int, int), |
| 730 | void *resize_ctx); |
| 731 | void term_provide_logctx(Terminal *term, void *logctx); |
| 732 | void term_set_focus(Terminal *term, int has_focus); |
| 733 | |
| 734 | /* |
| 735 | * Exports from logging.c. |
| 736 | */ |
| 737 | void *log_init(void *frontend, Config *cfg); |
| 738 | void log_free(void *logctx); |
| 739 | void log_reconfig(void *logctx, Config *cfg); |
| 740 | void logfopen(void *logctx); |
| 741 | void logfclose(void *logctx); |
| 742 | void logtraffic(void *logctx, unsigned char c, int logmode); |
| 743 | void logflush(void *logctx); |
| 744 | void log_eventlog(void *logctx, const char *string); |
| 745 | enum { PKT_INCOMING, PKT_OUTGOING }; |
| 746 | enum { PKTLOG_EMIT, PKTLOG_BLANK, PKTLOG_OMIT }; |
| 747 | struct logblank_t { |
| 748 | int offset; |
| 749 | int len; |
| 750 | int type; |
| 751 | }; |
| 752 | void log_packet(void *logctx, int direction, int type, |
| 753 | char *texttype, void *data, int len, |
| 754 | int n_blanks, const struct logblank_t *blanks); |
| 755 | |
| 756 | /* |
| 757 | * Exports from testback.c |
| 758 | */ |
| 759 | |
| 760 | extern Backend null_backend; |
| 761 | extern Backend loop_backend; |
| 762 | |
| 763 | /* |
| 764 | * Exports from raw.c. |
| 765 | */ |
| 766 | |
| 767 | extern Backend raw_backend; |
| 768 | |
| 769 | /* |
| 770 | * Exports from rlogin.c. |
| 771 | */ |
| 772 | |
| 773 | extern Backend rlogin_backend; |
| 774 | |
| 775 | /* |
| 776 | * Exports from telnet.c. |
| 777 | */ |
| 778 | |
| 779 | extern Backend telnet_backend; |
| 780 | |
| 781 | /* |
| 782 | * Exports from ssh.c. (NB the getline variables have to be GLOBAL |
| 783 | * so that PuTTYtel will still compile - otherwise it would depend |
| 784 | * on ssh.c.) |
| 785 | */ |
| 786 | |
| 787 | GLOBAL int (*ssh_get_line) (const char *prompt, char *str, int maxlen, |
| 788 | int is_pw); |
| 789 | GLOBAL int ssh_getline_pw_only; |
| 790 | extern Backend ssh_backend; |
| 791 | |
| 792 | /* |
| 793 | * Exports from ldisc.c. |
| 794 | */ |
| 795 | void *ldisc_create(Config *, Terminal *, Backend *, void *, void *); |
| 796 | void ldisc_free(void *); |
| 797 | void ldisc_send(void *handle, char *buf, int len, int interactive); |
| 798 | |
| 799 | /* |
| 800 | * Exports from ldiscucs.c. |
| 801 | */ |
| 802 | void lpage_send(void *, int codepage, char *buf, int len, int interactive); |
| 803 | void luni_send(void *, wchar_t * widebuf, int len, int interactive); |
| 804 | |
| 805 | /* |
| 806 | * Exports from sshrand.c. |
| 807 | */ |
| 808 | |
| 809 | void random_add_noise(void *noise, int length); |
| 810 | int random_byte(void); |
| 811 | void random_get_savedata(void **data, int *len); |
| 812 | extern int random_active; |
| 813 | /* The random number subsystem is activated if at least one other entity |
| 814 | * within the program expresses an interest in it. So each SSH session |
| 815 | * calls random_ref on startup and random_unref on shutdown. */ |
| 816 | void random_ref(void); |
| 817 | void random_unref(void); |
| 818 | |
| 819 | /* |
| 820 | * Exports from pinger.c. |
| 821 | */ |
| 822 | typedef struct pinger_tag *Pinger; |
| 823 | Pinger pinger_new(Config *cfg, Backend *back, void *backhandle); |
| 824 | void pinger_reconfig(Pinger, Config *oldcfg, Config *newcfg); |
| 825 | void pinger_free(Pinger); |
| 826 | |
| 827 | /* |
| 828 | * Exports from misc.c. |
| 829 | */ |
| 830 | |
| 831 | #include "misc.h" |
| 832 | |
| 833 | /* |
| 834 | * Exports from version.c. |
| 835 | */ |
| 836 | extern char ver[]; |
| 837 | |
| 838 | /* |
| 839 | * Exports from unicode.c. |
| 840 | */ |
| 841 | #ifndef CP_UTF8 |
| 842 | #define CP_UTF8 65001 |
| 843 | #endif |
| 844 | /* void init_ucs(void); -- this is now in platform-specific headers */ |
| 845 | int is_dbcs_leadbyte(int codepage, char byte); |
| 846 | int mb_to_wc(int codepage, int flags, char *mbstr, int mblen, |
| 847 | wchar_t *wcstr, int wclen); |
| 848 | int wc_to_mb(int codepage, int flags, wchar_t *wcstr, int wclen, |
| 849 | char *mbstr, int mblen, char *defchr, int *defused, |
| 850 | struct unicode_data *ucsdata); |
| 851 | wchar_t xlat_uskbd2cyrllic(int ch); |
| 852 | int check_compose(int first, int second); |
| 853 | int decode_codepage(char *cp_name); |
| 854 | const char *cp_enumerate (int index); |
| 855 | const char *cp_name(int codepage); |
| 856 | void get_unitab(int codepage, wchar_t * unitab, int ftype); |
| 857 | |
| 858 | /* |
| 859 | * Exports from wcwidth.c |
| 860 | */ |
| 861 | int wcwidth(wchar_t ucs); |
| 862 | int wcswidth(const wchar_t *pwcs, size_t n); |
| 863 | |
| 864 | /* |
| 865 | * Exports from mscrypto.c |
| 866 | */ |
| 867 | #ifdef MSCRYPTOAPI |
| 868 | int crypto_startup(); |
| 869 | void crypto_wrapup(); |
| 870 | #endif |
| 871 | |
| 872 | /* |
| 873 | * Exports from pageantc.c. |
| 874 | * |
| 875 | * agent_query returns 1 for here's-a-response, and 0 for query-in- |
| 876 | * progress. In the latter case there will be a call to `callback' |
| 877 | * at some future point, passing callback_ctx as the first |
| 878 | * parameter and the actual reply data as the second and third. |
| 879 | * |
| 880 | * The response may be a NULL pointer (in either of the synchronous |
| 881 | * or asynchronous cases), which indicates failure to receive a |
| 882 | * response. |
| 883 | */ |
| 884 | int agent_query(void *in, int inlen, void **out, int *outlen, |
| 885 | void (*callback)(void *, void *, int), void *callback_ctx); |
| 886 | int agent_exists(void); |
| 887 | |
| 888 | /* |
| 889 | * Exports from wildcard.c |
| 890 | */ |
| 891 | const char *wc_error(int value); |
| 892 | int wc_match(const char *wildcard, const char *target); |
| 893 | int wc_unescape(char *output, const char *wildcard); |
| 894 | |
| 895 | /* |
| 896 | * Exports from windlg.c |
| 897 | */ |
| 898 | void logevent(void *frontend, const char *); |
| 899 | /* |
| 900 | * verify_ssh_host_key() can return one of three values: |
| 901 | * |
| 902 | * - +1 means `key was OK' (either already known or the user just |
| 903 | * approved it) `so continue with the connection' |
| 904 | * |
| 905 | * - 0 means `key was not OK, abandon the connection' |
| 906 | * |
| 907 | * - -1 means `I've initiated enquiries, please wait to be called |
| 908 | * back via the provided function with a result that's either 0 |
| 909 | * or +1'. |
| 910 | */ |
| 911 | int verify_ssh_host_key(void *frontend, char *host, int port, char *keytype, |
| 912 | char *keystr, char *fingerprint, |
| 913 | void (*callback)(void *ctx, int result), void *ctx); |
| 914 | /* |
| 915 | * askalg has the same set of return values as verify_ssh_host_key. |
| 916 | */ |
| 917 | int askalg(void *frontend, const char *algtype, const char *algname, |
| 918 | void (*callback)(void *ctx, int result), void *ctx); |
| 919 | /* |
| 920 | * askappend can return four values: |
| 921 | * |
| 922 | * - 2 means overwrite the log file |
| 923 | * - 1 means append to the log file |
| 924 | * - 0 means cancel logging for this session |
| 925 | * - -1 means please wait. |
| 926 | */ |
| 927 | int askappend(void *frontend, Filename filename, |
| 928 | void (*callback)(void *ctx, int result), void *ctx); |
| 929 | |
| 930 | /* |
| 931 | * Exports from console.c (that aren't equivalents to things in |
| 932 | * windlg.c). |
| 933 | */ |
| 934 | extern int console_batch_mode; |
| 935 | int console_get_line(const char *prompt, char *str, int maxlen, int is_pw); |
| 936 | void console_provide_logctx(void *logctx); |
| 937 | int is_interactive(void); |
| 938 | |
| 939 | /* |
| 940 | * Exports from printing.c. |
| 941 | */ |
| 942 | typedef struct printer_enum_tag printer_enum; |
| 943 | typedef struct printer_job_tag printer_job; |
| 944 | printer_enum *printer_start_enum(int *nprinters); |
| 945 | char *printer_get_name(printer_enum *, int); |
| 946 | void printer_finish_enum(printer_enum *); |
| 947 | printer_job *printer_start_job(char *printer); |
| 948 | void printer_job_data(printer_job *, void *, int); |
| 949 | void printer_finish_job(printer_job *); |
| 950 | |
| 951 | /* |
| 952 | * Exports from cmdline.c (and also cmdline_error(), which is |
| 953 | * defined differently in various places and required _by_ |
| 954 | * cmdline.c). |
| 955 | */ |
| 956 | int cmdline_process_param(char *, char *, int, Config *); |
| 957 | void cmdline_run_saved(Config *); |
| 958 | void cmdline_cleanup(void); |
| 959 | extern char *cmdline_password; |
| 960 | #define TOOLTYPE_FILETRANSFER 1 |
| 961 | #define TOOLTYPE_NONNETWORK 2 |
| 962 | extern int cmdline_tooltype; |
| 963 | |
| 964 | void cmdline_error(char *, ...); |
| 965 | |
| 966 | /* |
| 967 | * Exports from config.c. |
| 968 | */ |
| 969 | struct controlbox; |
| 970 | void setup_config_box(struct controlbox *b, struct sesslist *sesslist, |
| 971 | int midsession, int protocol, int protcfginfo); |
| 972 | |
| 973 | /* |
| 974 | * Exports from minibidi.c. |
| 975 | */ |
| 976 | typedef struct bidi_char { |
| 977 | wchar_t origwc, wc; |
| 978 | unsigned short index; |
| 979 | } bidi_char; |
| 980 | int do_bidi(bidi_char *line, int count); |
| 981 | int do_shape(bidi_char *line, bidi_char *to, int count); |
| 982 | |
| 983 | /* |
| 984 | * X11 auth mechanisms we know about. |
| 985 | */ |
| 986 | enum { |
| 987 | X11_NO_AUTH, |
| 988 | X11_MIT, /* MIT-MAGIC-COOKIE-1 */ |
| 989 | X11_XDM, /* XDM-AUTHORIZATION-1 */ |
| 990 | X11_NAUTHS |
| 991 | }; |
| 992 | extern const char *const x11_authnames[]; /* declared in x11fwd.c */ |
| 993 | |
| 994 | /* |
| 995 | * Miscellaneous exports from the platform-specific code. |
| 996 | */ |
| 997 | Filename filename_from_str(const char *string); |
| 998 | const char *filename_to_str(const Filename *fn); |
| 999 | int filename_equal(Filename f1, Filename f2); |
| 1000 | int filename_is_null(Filename fn); |
| 1001 | char *get_username(void); /* return value needs freeing */ |
| 1002 | char *get_random_data(int bytes); /* used in cmdgen.c */ |
| 1003 | |
| 1004 | /* |
| 1005 | * Exports and imports from timing.c. |
| 1006 | * |
| 1007 | * schedule_timer() asks the front end to schedule a callback to a |
| 1008 | * timer function in a given number of ticks. The returned value is |
| 1009 | * the time (in ticks since an arbitrary offset) at which the |
| 1010 | * callback can be expected. This value will also be passed as the |
| 1011 | * `now' parameter to the callback function. Hence, you can (for |
| 1012 | * example) schedule an event at a particular time by calling |
| 1013 | * schedule_timer() and storing the return value in your context |
| 1014 | * structure as the time when that event is due. The first time a |
| 1015 | * callback function gives you that value or more as `now', you do |
| 1016 | * the thing. |
| 1017 | * |
| 1018 | * expire_timer_context() drops all current timers associated with |
| 1019 | * a given value of ctx (for when you're about to free ctx). |
| 1020 | * |
| 1021 | * run_timers() is called from the front end when it has reason to |
| 1022 | * think some timers have reached their moment, or when it simply |
| 1023 | * needs to know how long to wait next. We pass it the time we |
| 1024 | * think it is. It returns TRUE and places the time when the next |
| 1025 | * timer needs to go off in `next', or alternatively it returns |
| 1026 | * FALSE if there are no timers at all pending. |
| 1027 | * |
| 1028 | * timer_change_notify() must be supplied by the front end; it |
| 1029 | * notifies the front end that a new timer has been added to the |
| 1030 | * list which is sooner than any existing ones. It provides the |
| 1031 | * time when that timer needs to go off. |
| 1032 | * |
| 1033 | * *** FRONT END IMPLEMENTORS NOTE: |
| 1034 | * |
| 1035 | * There's an important subtlety in the front-end implementation of |
| 1036 | * the timer interface. When a front end is given a `next' value, |
| 1037 | * either returned from run_timers() or via timer_change_notify(), |
| 1038 | * it should ensure that it really passes _that value_ as the `now' |
| 1039 | * parameter to its next run_timers call. It should _not_ simply |
| 1040 | * call GETTICKCOUNT() to get the `now' parameter when invoking |
| 1041 | * run_timers(). |
| 1042 | * |
| 1043 | * The reason for this is that an OS's system clock might not agree |
| 1044 | * exactly with the timing mechanisms it supplies to wait for a |
| 1045 | * given interval. I'll illustrate this by the simple example of |
| 1046 | * Unix Plink, which uses timeouts to select() in a way which for |
| 1047 | * these purposes can simply be considered to be a wait() function. |
| 1048 | * Suppose, for the sake of argument, that this wait() function |
| 1049 | * tends to return early by 1%. Then a possible sequence of actions |
| 1050 | * is: |
| 1051 | * |
| 1052 | * - run_timers() tells the front end that the next timer firing |
| 1053 | * is 10000ms from now. |
| 1054 | * - Front end calls wait(10000ms), but according to |
| 1055 | * GETTICKCOUNT() it has only waited for 9900ms. |
| 1056 | * - Front end calls run_timers() again, passing time T-100ms as |
| 1057 | * `now'. |
| 1058 | * - run_timers() does nothing, and says the next timer firing is |
| 1059 | * still 100ms from now. |
| 1060 | * - Front end calls wait(100ms), which only waits for 99ms. |
| 1061 | * - Front end calls run_timers() yet again, passing time T-1ms. |
| 1062 | * - run_timers() says there's still 1ms to wait. |
| 1063 | * - Front end calls wait(1ms). |
| 1064 | * |
| 1065 | * If you're _lucky_ at this point, wait(1ms) will actually wait |
| 1066 | * for 1ms and you'll only have woken the program up three times. |
| 1067 | * If you're unlucky, wait(1ms) might do nothing at all due to |
| 1068 | * being below some minimum threshold, and you might find your |
| 1069 | * program spends the whole of the last millisecond tight-looping |
| 1070 | * between wait() and run_timers(). |
| 1071 | * |
| 1072 | * Instead, what you should do is to _save_ the precise `next' |
| 1073 | * value provided by run_timers() or via timer_change_notify(), and |
| 1074 | * use that precise value as the input to the next run_timers() |
| 1075 | * call. So: |
| 1076 | * |
| 1077 | * - run_timers() tells the front end that the next timer firing |
| 1078 | * is at time T, 10000ms from now. |
| 1079 | * - Front end calls wait(10000ms). |
| 1080 | * - Front end then immediately calls run_timers() and passes it |
| 1081 | * time T, without stopping to check GETTICKCOUNT() at all. |
| 1082 | * |
| 1083 | * This guarantees that the program wakes up only as many times as |
| 1084 | * there are actual timer actions to be taken, and that the timing |
| 1085 | * mechanism will never send it into a tight loop. |
| 1086 | * |
| 1087 | * (It does also mean that the timer action in the above example |
| 1088 | * will occur 100ms early, but this is not generally critical. And |
| 1089 | * the hypothetical 1% error in wait() will be partially corrected |
| 1090 | * for anyway when, _after_ run_timers() returns, you call |
| 1091 | * GETTICKCOUNT() and compare the result with the returned `next' |
| 1092 | * value to find out how long you have to make your next wait().) |
| 1093 | */ |
| 1094 | typedef void (*timer_fn_t)(void *ctx, long now); |
| 1095 | long schedule_timer(int ticks, timer_fn_t fn, void *ctx); |
| 1096 | void expire_timer_context(void *ctx); |
| 1097 | int run_timers(long now, long *next); |
| 1098 | void timer_change_notify(long next); |
| 1099 | |
| 1100 | #endif |