swank.R

   1 ### This program is free software; you can redistribute it and/or
   2 ### modify it under the terms of the GNU General Public Licence as
   3 ### published by the Free Software Foundation; either version 2 of the
   4 ### Licence, or (at your option) any later version.
   5 ###
   6 ### This program is distributed in the hope that it will be useful,
   7 ### but WITHOUT ANY WARRANTY; without even the implied warranty of
   8 ### MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   9 ### GNU General Public Licence for more details.
  10 ###
  11 ### A copy of version 2 of the GNU General Public Licence is available
  12 ### at <http://www.gnu.org/licenses/old-licenses/gpl-2.0.txt>; the
  13 ### latest version of the GNU General Public Licence is available at
  14 ### <http://www.gnu.org/licenses/gpl.txt>.
  15
  16 swank <- function(port=4005) {
  17   acceptConnections(port, FALSE)
  18 }
  19
  20 startSwank <- function(portFile) {
  21   acceptConnections(FALSE, portFile)
  22 }
  23
  24 acceptConnections <- function(port, portFile) {
  25   s <- socketConnection(host="localhost", server=TRUE, port=port, open="r+b")
  26   on.exit(close(s))
  27   serve(s)
  28 }
  29
  30 serve <- function(io) {
  31   mainLoop(io)
  32 }
  33
  34 mainLoop <- function(io) {
  35   slimeConnection <- new.env()
  36   slimeConnection$io <- io
  37   while(TRUE) {
  38     withRestarts(tryCatch(dispatch(slimeConnection, readPacket(io)),
  39                           swankTopLevel=function(c) NULL),
  40                  abort="return to SLIME's toplevel")
  41   }
  42 }
  43
  44 dispatch <- function(slimeConnection, event, sldbState=NULL) {
  45   str(event)
  46   kind <- event[[1]]
  47   if(kind == quote(`:emacs-rex`)) {
  48     do.call("emacsRex", c(list(slimeConnection), list(sldbState), event[-1]))
  49   }
  50 }
  51
  52 sendToEmacs <- function(slimeConnection, obj) {
  53   io <- slimeConnection$io
  54   str(obj)
  55   payload <- writeSexpToString(obj)
  56   writeChar(sprintf("%06x", nchar(payload)), io, eos=NULL)
  57   writeChar(payload, io, eos=NULL)
  58   flush(io)
  59   cat(sprintf("%06x", nchar(payload)), payload, sep="")
  60 }
  61
  62 callify <- function(form) {
  63   ## we implement here the conversion from Lisp S-expression (or list)
  64   ## expressions of code into our own, swankr, calling convention,
  65   ## with slimeConnection and sldbState as first and second arguments.
  66   ## as.call() gets us part of the way, but we need to walk the list
  67   ## recursively to mimic CL:EVAL; we need to avoid converting R
  68   ## special operators which we are punning (only `quote`, for now)
  69   ## into this calling convention.
  70   if(is.list(form)) {
  71     if(form[[1]] == quote(quote)) {
  72       as.call(form)
  73     } else {
  74       as.call(c(list(form[[1]], quote(slimeConnection), quote(sldbState)), lapply(form[-1], callify)))
  75     }
  76   } else {
  77     form
  78   }
  79 }
  80
  81 emacsRex <- function(slimeConnection, sldbState, form, pkg, thread, id, level=0) {
  82   ok <- FALSE
  83   value <- NULL
  84   tryCatch({
  85     withCallingHandlers({
  86       call <- callify(form)
  87       value <- eval(call)
  88       ok <- TRUE
  89     }, error=function(c) {
  90       newSldbState <- makeSldbState(c, if(is.null(sldbState)) 0 else sldbState$level+1, id)
  91       withRestarts(sldbLoop(slimeConnection, newSldbState, id), abort=paste("return to sldb level", newSldbState$level)) })},
  92     finally=sendToEmacs(slimeConnection, list(quote(`:return`), if(ok) list(quote(`:ok`), value) else list(quote(`:abort`)), id)))
  93 }
  94
  95 makeSldbState <- function(condition, level, id) {
  96   calls <- rev(sys.calls())[-1]
  97   frames <- rev(sys.frames())[-1]
  98   restarts <- rev(computeRestarts(condition))[-1]
  99   ret <- list(condition=condition, level=level, id=id, restarts=restarts, calls=calls, frames=frames)
 100   class(ret) <- c("sldbState", class(ret))
 101   ret
 102 }
 103
 104 sldbLoop <- function(slimeConnection, sldbState, id) {
 105   tryCatch({
 106     io <- slimeConnection$io
 107     sendToEmacs(slimeConnection, c(list(quote(`:debug`), id, sldbState$level), `swank:debugger-info-for-emacs`(slimeConnection, sldbState)))
 108     sendToEmacs(slimeConnection, list(quote(`:debug-activate`), id, sldbState$level, FALSE))
 109     while(TRUE) {
 110       dispatch(slimeConnection, readPacket(io), sldbState)
 111     }
 112   }, finally=sendToEmacs(slimeConnection, c(list(quote(`:debug-return`), id, sldbState$level, FALSE))))
 113 }
 114
 115 readPacket <- function(io) {
 116   socketSelect(list(io))
 117   header <- readChunk(io, 6)
 118   len <- strtoi(header, base=16)
 119   payload <- readChunk(io, len)
 120   readSexpFromString(payload)
 121 }
 122
 123 readChunk <- function(io, len) {
 124   buffer <- readChar(io, len)
 125   if(nchar(buffer) != len) {
 126     stop("short read in readChunk")
 127   }
 128   buffer
 129 }
 130
 131 readSexpFromString <- function(string) {
 132   pos <- 1
 133   read <- function() {
 134     skipWhitespace()
 135     char <- substr(string, pos, pos)
 136     switch(char,
 137            "("=readList(),
 138            "\""=readString(),
 139            "'"=readQuote(),
 140            {
 141              if(pos > nchar(string))
 142                stop("EOF during read")
 143              obj <- readNumberOrSymbol()
 144              if(obj == quote(`.`)) {
 145                stop("Consing dot not implemented")
 146              }
 147              obj
 148            })
 149   }
 150   skipWhitespace <- function() {
 151     while(substr(string, pos, pos) %in% c(" ", "\t", "\n")) {
 152       pos <<- pos + 1
 153     }
 154   }
 155   readList <- function() {
 156     ret <- list()
 157     pos <<- pos + 1
 158     while(TRUE) {
 159       skipWhitespace()
 160       char <- substr(string, pos, pos)
 161       if(char == ")") {
 162         pos <<- pos + 1
 163         break
 164       } else {
 165         obj <- read()
 166         if(length(obj) == 1 && obj == quote(`.`)) {
 167           stop("Consing dot not implemented")
 168         }
 169         ret <- c(ret, list(obj))
 170       }
 171     }
 172     ret
 173   }
 174   readString <- function() {
 175     ret <- ""
 176     addChar <- function(c) { ret <<- paste(ret, c, sep="") }
 177     while(TRUE) {
 178       pos <<- pos + 1
 179       char <- substr(string, pos, pos)
 180       switch(char,
 181              "\""={ pos <<- pos + 1; break },
 182              "\\"={ pos <<- pos + 1
 183                     char2 <- substr(string, pos, pos)
 184                     switch(char2,
 185                            "\""=addChar(char2),
 186                            "\\"=addChar(char2),
 187                            stop("Unrecognized escape character")) },
 188              addChar(char))
 189     }
 190     ret
 191   }
 192   readNumberOrSymbol <- function() {
 193     token <- readToken()
 194     if(nchar(token)==0) {
 195       stop("End of file reading token")
 196     } else if(grepl("^[0-9]+$", token)) {
 197       strtoi(token)
 198     } else if(grepl("^[0-9]+\\.[0-9]+$", token)) {
 199       as.double(token)
 200     } else {
 201       as.name(token)
 202     }
 203   }
 204   readToken <- function() {
 205     token <- ""
 206     while(TRUE) {
 207       char <- substr(string, pos, pos)
 208       if(char == "") {
 209         break;
 210       } else if(char %in% c(" ", "\n", "\t", "(", ")", "\"", "'")) {
 211         break;
 212       } else {
 213         token <- paste(token, char, sep="")
 214         pos <<- pos + 1
 215       }
 216     }
 217     token
 218   }
 219   read()
 220 }
 221
 222 writeSexpToString <- function(obj) {
 223   writeSexpToStringLoop <- function(obj) {
 224     switch(typeof(obj),
 225            "character"={ string <- paste(string, "\"", gsub("([\"\\])", "\\\\\\1", obj), "\"", sep="") },
 226            "list"={ string <- paste(string, "(", sep="")
 227                     max <- length(obj)
 228                     if(max > 0) {
 229                       for(i in 1:max) {
 230                         string <- paste(string, writeSexpToString(obj[[i]]), sep="")
 231                         if(i != max) {
 232                           string <- paste(string, " ", sep="")
 233                         }
 234                       }
 235                     }
 236                     string <- paste(string, ")", sep="") },
 237            "symbol"={ string <- paste(string, as.character(obj), sep="") },
 238            "logical"={ string <- if(obj) { paste(string, "t", sep="") } else { paste(string, "nil", sep="") }},
 239            "double"={ string <- paste(string, as.character(obj), sep="") },
 240            "integer"={ string <- paste(string, as.character(obj), sep="") },
 241            stop(paste("can't write object ", obj, sep="")))
 242     string
 243   }
 244   string <- ""
 245   writeSexpToStringLoop(obj)
 246 }
 247
 248 withOutputToString <- function(expr) {
 249   call <- substitute(expr)
 250   f <- fifo("")
 251   sink(f)
 252   tryCatch({ tryCatch(eval.parent(call), finally=sink())
 253              readLines(f) },
 254            finally=close(f))
 255 }
 256
 257 printToString <- function(val) {
 258   withOutputToString(str(val, indent.str="", list.len=5, max.level=2))
 259 }
 260
 261 `swank:connection-info` <- function (slimeConnection, sldbState) {
 262   list(quote(`:pid`), Sys.getpid(),
 263        quote(`:package`), list(quote(`:name`), "R", quote(`:prompt`), "R> "),
 264        quote(`:lisp-implementation`), list(quote(`:type`), "R",
 265                                            quote(`:name`), "R",
 266                                            quote(`:version`), paste(R.version$major, R.version$minor, sep=".")))
 267 }
 268
 269 `swank:swank-require` <- function (slimeConnection, sldbState, contribs) {
 270   for(contrib in contribs) {
 271     filename <- sprintf("%s.R", as.character(contrib))
 272     if(file.exists(filename)) {
 273       source(filename, verbose=TRUE)
 274     }
 275   }
 276   list()
 277 }
 278
 279 `swank:create-repl` <- function(slimeConnection, sldbState, env, ...) {
 280   list("R", "R")
 281 }
 282
 283 makeReplResult <- function(value) {
 284   string <- printToString(value)
 285   list(quote(`:write-string`), paste(string, collapse="\n"),
 286        quote(`:repl-result`))
 287 }
 288
 289 makeReplResultFunction <- makeReplResult
 290
 291 sendReplResult <- function(slimeConnection, value) {
 292   result <- makeReplResultFunction(value)
 293   sendToEmacs(slimeConnection, result)
 294 }
 295
 296 sendReplResultFunction <- sendReplResult
 297
 298 `swank:listener-eval` <- function(slimeConnection, sldbState, string) {
 299   string <- gsub("#\\.\\(swank:lookup-presented-object-or-lose([^)]*)\\)", ".(`swank:lookup-presented-object-or-lose`(slimeConnection, sldbState,\\1))", string)
 300   expr <- parse(text=string)[[1]]
 301   lookedup <- do.call("bquote", list(expr))
 302   value <- eval(lookedup, envir = globalenv())
 303   sendReplResultFunction(slimeConnection, value)
 304   list()
 305 }
 306
 307 `swank:autodoc` <- function(slimeConnection, sldbState, rawForm, ...) {
 308   "No Arglist Information"
 309 }
 310
 311 `swank:operator-arglist` <- function(slimeConnection, sldbState, op, package) {
 312   list()
 313 }
 314
 315 `swank:throw-to-toplevel` <- function(slimeConnection, sldbState) {
 316   condition <- simpleCondition("Throw to toplevel")
 317   class(condition) <- c("swankTopLevel", class(condition))
 318   signalCondition(condition)
 319 }
 320
 321 `swank:backtrace` <- function(slimeConnection, sldbState, from=0, to=NULL) {
 322   calls <- sldbState$calls
 323   if(is.null(to)) to <- length(calls)
 324   from <- from+1
 325   calls <- lapply(calls[from:to],
 326                   { frameNumber <- from-1;
 327                     function (x) {
 328                       ret <- list(frameNumber, paste(format(x), sep="", collapse=" "))
 329                       frameNumber <<- 1+frameNumber
 330                       ret
 331                     }
 332                   })
 333 }
 334
 335 computeRestartsForEmacs <- function (sldbState) {
 336   lapply(sldbState$restarts,
 337          function(x) {
 338            ## this is all a little bit internalsy
 339            restartName <- x[[1]][[1]]
 340            description <- restartDescription(x)
 341            list(restartName, if(is.null(description)) restartName else description)
 342          })
 343 }
 344
 345 `swank:debugger-info-for-emacs` <- function(slimeConnection, sldbState, from=0, to=NULL) {
 346   list(list(as.character(sldbState$condition), sprintf("  [%s]", class(sldbState$condition)[[1]]), FALSE),
 347        computeRestartsForEmacs(sldbState),
 348        `swank:backtrace`(slimeConnection, sldbState, from, to),
 349        list(sldbState$id))
 350 }
 351
 352 `swank:invoke-nth-restart-for-emacs` <- function(slimeConnection, sldbState, level, n) {
 353   if(sldbState$level == level) {
 354     invokeRestart(sldbState$restarts[[n+1]])
 355   }
 356 }
 357
 358 `swank:frame-source-location` <- function(slimeConnection, sldbState, n) {
 359   call <- sldbState$calls[[n+1]]
 360   srcref <- attr(call, "srcref")
 361   srcfile <- attr(srcref, "srcfile")
 362   if(is.null(srcfile)) {
 363     list(quote(`:error`), "no srcfile")
 364   } else {
 365     list(quote(`:location`),
 366          list(quote(`:file`), sprintf("%s/%s", srcfile$wd, srcfile$filename)),
 367          list(quote(`:line`), srcref[[1]], srcref[[2]]-1),
 368          FALSE)
 369   }
 370 }
 371
 372 `swank:buffer-first-change` <- function(slimeConnection, sldbState, filename) {
 373   FALSE
 374 }
 375
 376 `swank:eval-string-in-frame` <- function(slimeConnection, sldbState, string, index) {
 377   frame <- sldbState$frames[[1+index]]
 378   withRetryRestart("retry SLIME interactive evaluation request",
 379                    value <- eval(parse(text=string), envir=frame))
 380   printToString(value)
 381 }
 382
 383 `swank:frame-locals-and-catch-tags` <- function(slimeConnection, sldbState, index) {
 384   str(sldbState$frames)
 385   frame <- sldbState$frames[[1+index]]
 386   objs <- ls(envir=frame)
 387   list(lapply(objs, function(name) { list(quote(`:name`), name,
 388                                           quote(`:id`), 0,
 389                                           quote(`:value`), paste(printToString(eval(parse(text=name), envir=frame)), sep="", collapse="\n")) }),
 390        list())
 391 }
 392
 393 `swank:simple-completions` <- function(slimeConnection, sldbState, prefix, package) {
 394   ## fails multiply if prefix contains regexp metacharacters
 395   matches <- apropos(sprintf("^%s", prefix), ignore.case=FALSE)
 396   nmatches <- length(matches)
 397   if(nmatches == 0) {
 398     list(list(), "")
 399   } else {
 400     longest <- matches[order(nchar(matches))][1]
 401     while(length(grep(sprintf("^%s", longest), matches)) < nmatches) {
 402       longest <- substr(longest, 1, nchar(longest)-1)
 403     }
 404     list(as.list(matches), longest)
 405   }
 406 }
 407
 408 `swank:compile-string-for-emacs` <- function(slimeConnection, sldbState, string, buffer, position, filename, policy) {
 409   # FIXME: I think in parse() here we can use srcref to associate
 410   # buffer/filename/position to the objects.  Or something.
 411   withRestarts({ times <- system.time(eval(parse(text=string), envir = globalenv())) },
 412                abort="abort compilation")
 413   list(quote(`:compilation-result`), list(), TRUE, times[3])
 414 }
 415
 416 withRetryRestart <- function(description, expr) {
 417   call <- substitute(expr)
 418   retry <- TRUE
 419   while(retry) {
 420     retry <- FALSE
 421     withRestarts(eval.parent(call),
 422                  retry=list(description=description,
 423                    handler=function() retry <<- TRUE))
 424   }
 425 }
 426
 427 `swank:interactive-eval` <-  function(slimeConnection, sldbState, string) {
 428   withRetryRestart("retry SLIME interactive evaluation request",
 429                    value <- eval(parse(text=string), envir=globalenv()))
 430   printToString(value)
 431 }
 432
 433 `swank:eval-and-grab-output` <- function(slimeConnection, sldbState, string) {
 434   withRetryRestart("retry SLIME interactive evaluation request",
 435                    { output <-
 436                        withOutputToString(value <- eval(parse(text=string),
 437                                                         envir=globalenv())) })
 438   list(output, printToString(value))
 439 }
 440
 441 `swank:find-definitions-for-emacs` <- function(slimeConnection, sldbState, string) {
 442   if(exists(string, envir = globalenv())) {
 443     thing <- get(string, envir = globalenv())
 444     if(inherits(thing, "function")) {
 445       body <- body(thing)
 446       srcref <- attr(body, "srcref")
 447       srcfile <- attr(body, "srcfile")
 448       if(is.null(srcfile)) {
 449         list()
 450       } else {
 451         filename <- get("filename", srcfile)
 452         list(list(sprintf("function %s", string),
 453                   list(quote(`:location`),
 454                        list(quote(`:file`), sprintf("%s/%s", srcfile$wd, srcfile$filename)),
 455                        list(quote(`:line`), srcref[[2]][[1]], srcref[[2]][[2]]-1),
 456                        list())))
 457       }
 458     } else {
 459       list()
 460     }
 461   } else {
 462     list()
 463   }
 464 }
 465
 466 `swank:value-for-editing` <- function(slimeConnection, sldbState, string) {
 467   paste(deparse(eval(parse(text=string), envir = globalenv()), control="all"),
 468         collapse="\n", sep="")
 469 }
 470
 471 `swank:commit-edited-value` <- function(slimeConnection, sldbState, string, value) {
 472   eval(parse(text=sprintf("%s <- %s", string, value)), envir = globalenv())
 473   TRUE
 474 }
 475
 476 resetInspector <- function(slimeConnection) {
 477   assign("istate", list(), envir=slimeConnection)
 478   assign("inspectorHistory", NULL, envir=slimeConnection)
 479 }
 480
 481 `swank:init-inspector` <- function(slimeConnection, sldbState, string) {
 482   withRetryRestart("retry SLIME inspection request",
 483                    { resetInspector(slimeConnection)
 484                      value <- inspectObject(slimeConnection, eval(parse(text=string), envir=globalenv()))
 485                    })
 486   value
 487 }
 488
 489 inspectObject <- function(slimeConnection, object) {
 490   previous <- slimeConnection$istate
 491   slimeConnection$istate <- new.env()
 492   slimeConnection$istate$object <- object
 493   slimeConnection$istate$previous <- previous
 494   slimeConnection$istate$content <- emacsInspect(object)
 495   if(!(object %in% slimeConnection$inspectorHistory)) {
 496     slimeConnection$inspectorHistory <- c(slimeConnection$inspectorHistory, object)
 497   }
 498   if(!is.null(slimeConnection$istate$previous)) {
 499     slimeConnection$istate$previous$`next` <- slimeConnection$istate
 500   }
 501   istateToElisp(slimeConnection$istate)
 502 }
 503
 504 valuePart <- function(istate, object, string) {
 505   list(quote(`:value`),
 506        if(is.null(string)) paste(printToString(object),collapse=" ") else string,
 507        assignIndexInParts(object, istate))
 508 }
 509
 510 preparePart <- function(istate, part) {
 511   if(is.character(part)) {
 512     list(part)
 513   } else {
 514     switch(as.character(part[[1]]),
 515            `:newline` = list("\n"),
 516            `:value` = valuePart(istate, part[[2]], part[[3]]),
 517            `:line` = list(printToString(part[[2]]), ": ",
 518              valuePart(istate, part[[3]], NULL), "\n"))
 519   }
 520 }
 521
 522 prepareRange <- function(istate, start, end) {
 523   range <- istate$content[start+1:min(end+1, length(istate$content))]
 524   ps <- NULL
 525   for(part in range) {
 526     ps <- c(ps, preparePart(istate, part))
 527   }
 528   list(ps, if(length(ps)<end-start) { start+length(ps) } else { end+1000 },
 529        start, end)
 530 }
 531
 532 assignIndexInParts <- function(object, istate) {
 533   ret <- 1+length(istate$parts)
 534   istate$parts <- c(istate$parts, list(object))
 535   ret
 536 }
 537
 538 istateToElisp <- function(istate) {
 539   list(quote(`:title`), deparse(istate$object, control="all", nlines=1),
 540        quote(`:id`), assignIndexInParts(istate$object, istate),
 541        quote(`:content`), prepareRange(istate, 0, 500))
 542 }
 543
 544 emacsInspect <- function(object) {
 545   UseMethod("emacsInspect")
 546 }
 547
 548 emacsInspect.default <- function(thing) {
 549   c(list(paste("a ", class(thing)[[1]], sep=""), list(quote(`:newline`))))
 550 }
 551
 552 emacsInspect.list <- function(list) {
 553   c(list("a list", list(quote(`:newline`))),
 554     mapply(function(name, value) { list(list(quote(`:line`), name, value)) },
 555            names(list), list))
 556 }
 557
 558 emacsInspect.numeric <- function(numeric) {
 559   c(list("a numeric", list(quote(`:newline`))),
 560     mapply(function(name, value) { list(list(quote(`:line`), name, value)) },
 561            (1:length(numeric)), numeric))
 562 }
 563
 564 `swank:quit-inspector` <- function(slimeConnection, sldbState) {
 565   resetInspector(slimeConnection)
 566   FALSE
 567 }
 568
 569 `swank:inspector-nth-part` <- function(slimeConnection, sldbState, index) {
 570   slimeConnection$istate$parts[[index]]
 571 }
 572
 573 `swank:inspect-nth-part` <- function(slimeConnection, sldbState, index) {
 574   object <- `swank:inspector-nth-part`(slimeConnection, sldbState, index)
 575   inspectObject(slimeConnection, object)
 576 }
 577
 578 `swank:inspector-pop` <- function(slimeConnection, sldbState) {
 579   if(!is.null(slimeConnection$istate$previous)) {
 580     slimeConnection$istate <- slimeConnection$istate$previous
 581     istateToElisp(slimeConnection$istate)
 582   } else {
 583     FALSE
 584   }
 585 }
 586
 587 `swank:inspector-next` <- function(slimeConnection, sldbState) {
 588   if(!is.null(slimeConnection$istate$`next`)) {
 589     slimeConnection$istate <- slimeConnection$istate$`next`
 590     istateToElisp(slimeConnection$istate)
 591   } else {
 592     FALSE
 593   }
 594 }
 595
 596 `swank:inspector-eval` <- function(slimeConnection, sldbState, string) {
 597   expr <- parse(text=string)[[1]]
 598   object <- slimeConnection$istate$object
 599   if(inherits(object, "list")|inherits(object, "environment")) {
 600     substituted <- substituteDirect(expr, object)
 601     eval(substituted, envir=globalenv())
 602   } else {
 603     eval(expr, envir=globalenv())
 604   }
 605 }
 606
 607 `swank:inspect-current-condition` <- function(slimeConnection, sldbState) {
 608   resetInspector(slimeConnection)
 609   inspectObject(slimeConnection, sldbState$condition)
 610 }
 611
 612 `swank:inspect-frame-var` <- function(slimeConnection, sldbState, frame, var) {
 613   resetInspector(slimeConnection)
 614   frame <- sldbState$frames[[1+frame]]
 615   name <- ls(envir=frame)[[1+var]]
 616   object <- get(name, envir=frame)
 617   inspectObject(slimeConnection, object)
 618 }