document width limit on console lines, use CONSOLE_BUFFER_LENGTH in o…

…ne place.

Windows FileReadConsole could overflow its buffer (< 1024 bytes)


git-svn-id: https://svn.r-project.org/R/trunk@38967 00db46b3-68df-0310-9c12-caf00c1e9a41

doc/manual/R-exts.texi

@@ -8947,7 +8947,8 @@ void Rf_endEmbeddedR(int fatal);
 @noindent
 which is an entry point in @file{R.dll}.  Examples of its use (and a
 suitable @file{Makefile.win}) can be found in the @file{tests/Embedding}
-directory of the sources.
+directory of the sources.  You may need to ensure that
+@file{@var{R_HOME}/bin} is in your @env{PATH} so the R DLLs are found.
 
 Examples of calling @file{R.dll} directly are provided in the directory
 @file{src/@/gnuwin32/@/front-ends}, including @file{Rproxy.dll} used by

doc/manual/R-intro.texi

@@ -475,6 +475,9 @@ command is syntactically complete.  This prompt may be changed by the
 user.  We will generally omit the continuation prompt
 and indicate continuation by simple indenting.
 
+Command lines entered at the console are limited to 1024 bytes (not
+characters): many of the consoles will not allow you to enter more.
+
 @node Recall and correction of previous commands, Executing commands from or diverting output to a file, R commands; case sensitivity etc, Introduction and preliminaries
 @section Recall and correction of previous commands
 
@@ -500,9 +503,9 @@ statistical system FAQ}.
 @section Executing commands from or diverting output to a file
 @cindex Diverting input and output
 
-If commands are stored in an external file, say @file{commands.R} in the
-working directory @file{work}, they may be executed at any time in an
-@R{} session with the command
+If commands@footnote{of unlimited length.} are stored in an external
+file, say @file{commands.R} in the working directory @file{work}, they
+may be executed at any time in an @R{} session with the command
 
 @example
 > source("commands.R")
@@ -6949,8 +6952,10 @@ skipped: this can be useful to retrieve values from it with
 @end table
 
 Note that input and output can be redirected in the usual way (using
-@samp{<} and @samp{>}).  Warning and error messages are sent to the
-error channel (@code{stderr}) except on Windows 9X/ME.
+@samp{<} and @samp{>}), but the line width limit of 1024 bytes still
+applies (and lines will be truncated with no warning).  Warning and error
+messages are sent to the error channel (@code{stderr}) except on Windows
+9X/ME.
 
 The command @code{R CMD} allows the invocation of various tools which
 are useful in conjunction with @R{}, but not intended to be called

src/gnuwin32/CHANGES

@@ -33,6 +33,9 @@ place, so those functions are available while waiting for an event.
 iconv.dll has been updated to 1.11, which has some improvements for
 CJK languages under Windows (e.g. support for the Euro).
 
+Using lines of more than 1000 chars in an R file in batch mode could
+crash R.
+
 
 Installing packages
 -------------------

src/gnuwin32/console.c

@@ -1544,7 +1544,8 @@ int consolereads(control c, char *prompt, char *buf, int len, int addtohistory)
 		    }
 		    cur_line[max_byte] = '\n';
 		    cur_line[max_byte + 1] = '\0';
-		    strcpy(buf, cur_line);
+		    /* just to be safe: we have not allowed max_byte > len-2 */
+		    strncpy(buf, cur_line, len);
 		    p->r = -1;
 		    cur_line[max_byte] = '\0';
 		    if (max_byte && addtohistory)  gl_histadd(cur_line);

src/gnuwin32/system.c

@@ -258,9 +258,9 @@ ThreadedReadConsole(char *prompt, char *buf, int len, int addtohistory)
 static int
 CharReadConsole(char *prompt, char *buf, int len, int addtohistory)
 {
-   int res = getline(prompt,buf,len);
-   if (addtohistory) gl_histadd(buf);
-   return !res;
+    int res = getline(prompt,buf,len);
+    if (addtohistory) gl_histadd(buf);
+    return !res;
 }
 
 /*3: (as InThreadReadConsole) and 4: non-interactive */
@@ -270,17 +270,16 @@ static int
 FileReadConsole(char *prompt, char *buf, int len, int addhistory)
 {
     int ll, err = 0;
-    char inbuf[1001];
+
     if (!R_Slave) {
 	fputs(prompt, stdout);
 	fflush(stdout);
     }
-    if (fgets(inbuf, len, stdin) == NULL)
-	return 0;
+    if (fgets(buf, len, stdin) == NULL) return 0;
     /* translate if necessary */
     if(strlen(R_StdinEnc) && strcmp(R_StdinEnc, "native.enc")) {
-	size_t res, inb = strlen(inbuf), onb = len;
-	char *ib = inbuf, *ob = buf;
+	size_t res, inb = strlen(buf), onb = len;
+	char *ib = buf, *ob = buf;
 	if(!cd) {
 	    cd = Riconv_open("", R_StdinEnc);
 	    if(!cd) error(_("encoding '%s' is not recognised"), R_StdinEnc);
@@ -289,13 +288,14 @@ FileReadConsole(char *prompt, char *buf, int len, int addhistory)
 	*ob = '\0';
 	err = res == (size_t)(-1);
 	/* errors lead to part of the input line being ignored */
-	if(err) fputs(_("<ERROR: invalid input in encoding> "), stdout);
-    } else strncpy(buf, inbuf, strlen(inbuf)+1);
-    
+	if(err) fputs(_("<ERROR: invalid input in encoding>\n"), stdout);
+    }
+
 /* according to system.txt, should be terminated in \n, so check this
    at eof or error */
     ll = strlen((char *)buf);
-    if ((err || feof(stdin)) && buf[ll - 1] != '\n' && ll < len) {
+    if ((err || feof(stdin))
+	&& buf[ll - 1] != '\n' && ll < len) {
 	buf[ll++] = '\n'; buf[ll] = '\0';
     }
     if (!R_Interactive && !R_Slave)
@@ -630,7 +630,7 @@ void R_SetWin32(Rstart Rp)
 	R_CStackStart = top;
 	R_CStackLimit = top - bottom;
     }
-    
+
     R_CStackDir = 1;
     R_Home = Rp->rhome;
     if(strlen(R_Home) >= MAX_PATH) R_Suicide("Invalid R_HOME");
@@ -939,7 +939,7 @@ int cmdlineoptions(int ac, char **av)
  *  Since users' expectations for save/no-save will differ, we decided
  *  that they should be forced to specify in the non-interactive case.
  */
-    if (!R_Interactive && Rp->SaveAction != SA_SAVE && 
+    if (!R_Interactive && Rp->SaveAction != SA_SAVE &&
 	Rp->SaveAction != SA_NOSAVE)
 	R_Suicide(_("you must specify '--save', '--no-save' or '--vanilla'"));
 

src/include/Defn.h

@@ -790,6 +790,8 @@ LibExtern AccuracyInfo R_AccuracyInfo;
 #define	R_FILE		2
 #define R_TEXT		3
 
+/* The maximum length of input line which will be asked for */
+#define CONSOLE_BUFFER_SIZE 1024
 int	R_ReadConsole(char*, unsigned char*, int, int);
 void	R_WriteConsole(char*, int);
 void	R_ResetConsole(void);

src/library/base/man/source.Rd

@@ -59,6 +59,9 @@ source(file, local = FALSE, echo = verbose, print.eval = echo,
   used a guide.  If \code{encoding} has two or more elements, they are
   tried in turn until the file/URL can be read without error in the
   trial encoding.
+
+  Unlike input from a console, lines in the file or on a connection can
+  contain an unlimited number of characters.
 }
 \references{
   Becker, R. A., Chambers, J. M. and Wilks, A. R. (1988)

src/main/connections.c

@@ -1614,9 +1614,6 @@ static Rconnection newclp(char *url, char *mode)
 
 /* ------------------- terminal connections --------------------- */
 
-/* The size of the console buffer */
-#define CONSOLE_BUFFER_SIZE	1024
-
 static unsigned char  ConsoleBuf[CONSOLE_BUFFER_SIZE];
 static unsigned char *ConsoleBufp;
 static int  ConsoleBufCnt;

src/main/main.c

@@ -51,6 +51,7 @@ void attribute_hidden nl_Rdummy()
 }
 #endif
 
+
 /* The 'real' main() program is in ../<SYSTEM>/system.c */
 /* e.g. ../unix/system.c */
 
@@ -202,7 +203,8 @@ Rf_ReplIteration(SEXP rho, int savestack, int browselevel, R_ReplState *state)
     if(!*state->bufp) {
 	    R_Busy(0);
 	    if (R_ReadConsole(R_PromptString(browselevel, state->prompt_type),
-			      state->buf, 1024, 1) == 0) return(-1);
+			      state->buf, CONSOLE_BUFFER_SIZE, 1) == 0)
+		return(-1);
 	    state->bufp = state->buf;
     }
 #ifdef SHELL_ESCAPE
@@ -294,7 +296,8 @@ static void R_ReplConsole(SEXP rho, int savestack, int browselevel)
 
     R_IoBufferWriteReset(&R_ConsoleIob);
     state.buf[0] = '\0';
-    state.buf[1024] = '\0'; /* stopgap measure if line > 1024 chars */
+    state.buf[CONSOLE_BUFFER_SIZE] = '\0'; 
+    /* stopgap measure if line > CONSOLE_BUFFER_SIZE chars */
     state.bufp = state.buf;
     if(R_Verbose)
 	REprintf(" >R_ReplConsole(): before \"for(;;)\" {main.c}\n");
@@ -306,7 +309,7 @@ static void R_ReplConsole(SEXP rho, int savestack, int browselevel)
 }
 
 
-static unsigned char DLLbuf[1024], *DLLbufp;
+static unsigned char DLLbuf[CONSOLE_BUFFER_SIZE], *DLLbufp;
 
 void R_ReplDLLinit()
 {
@@ -327,7 +330,8 @@ int R_ReplDLLdo1()
 
     if(!*DLLbufp) {
 	R_Busy(0);
-	if (R_ReadConsole(R_PromptString(0, prompt_type), DLLbuf, 1024, 1) == 0)
+	if (R_ReadConsole(R_PromptString(0, prompt_type), DLLbuf,
+			  CONSOLE_BUFFER_SIZE, 1) == 0)
 	    return -1;
 	DLLbufp = DLLbuf;
     }
@@ -433,12 +437,11 @@ static void win32_segv(int signum)
 
    2005-12-17 BDR */
 
-#define CONSOLE_BUFFER_SIZE 1024
-static unsigned char  ConsoleBuf[CONSOLE_BUFFER_SIZE];
+static unsigned char ConsoleBuf[CONSOLE_BUFFER_SIZE];
 
 static void sigactionSegv(int signum, siginfo_t *ip, void *context)
 {
-    char *s, buf[1024];
+    char *s, buf[MAX_PATH+20];
 
     /* First check for stack overflow if we know the stack position.
        We assume anything within 16Mb beyond the stack end is a stack overflow.
@@ -568,7 +571,7 @@ static void sigactionSegv(int signum, siginfo_t *ip, void *context)
 	}
     }
     REprintf("aborting ...\n");
-    snprintf(buf, 1024, "rm -rf %s", R_TempDir);
+    snprintf(buf, MAX_PATH+20, "rm -rf %s", R_TempDir);
     R_system(buf);
     /* now do normal behaviour, e.g. core dump */
     signal(signum, SIG_DFL);

src/main/scan.c

@@ -45,7 +45,6 @@
 /* The size of vector initially allocated by scan */
 #define SCAN_BLOCKSIZE		1000
 /* The size of the console buffer */
-#define CONSOLE_BUFFER_SIZE	1024
 #define CONSOLE_PROMPT_SIZE	256
 
 #define NO_COMCHAR 100000 /* won't occur even in Unicode */