Add very limited support for DCS Request Termcap/Terminfo String (bug 2220)

Author: gnachman

NSStringITerm.h

@@ -109,6 +109,10 @@ int decode_utf8_char(const unsigned char * restrict datap,
 // Fonts are encoded as strings when stored in a profile. This returns the font for such a string.
 - (NSFont *)fontValue;
 
+// Returns a 2-hex-chars-per-char encoding of this string.
+- (NSString *)hexEncodedString;
++ (NSString *)stringWithHexEncodedString:(NSString *)hexEncodedString;
+
 @end
 
 @interface NSMutableString (iTerm)

NSStringITerm.m

@@ -878,6 +878,27 @@ - (NSFont *)fontValue {
     return aFont;
 }
 
+- (NSString *)hexEncodedString {
+    NSMutableString *result = [NSMutableString string];
+    for (int i = 0; i < self.length; i++) {
+        [result appendFormat:@"%02X", [self characterAtIndex:i]];
+    }
+    return [[result copy] autorelease];
+}
+
++ (NSString *)stringWithHexEncodedString:(NSString *)hexEncodedString {
+    NSMutableString *result = [NSMutableString string];
+    for (int i = 0; i + 1 < hexEncodedString.length; i += 2) {
+        char buffer[3] = { [hexEncodedString characterAtIndex:i],
+                           [hexEncodedString characterAtIndex:i + 1],
+                           0 };
+        int value;
+        sscanf(buffer, "%02x", &value);
+        [result appendFormat:@"%C", (unichar)value];
+    }
+    return [[result copy] autorelease];
+}
+
 @end
 
 @implementation NSMutableString (iTerm)

VT100DCSParser.h

@@ -9,6 +9,12 @@
 #import <Foundation/Foundation.h>
 #import "VT100Token.h"
 
+typedef enum {
+    kDcsTermcapTerminfoRequestUnrecognizedName,
+    kDcsTermcapTerminfoRequestTerminalName,
+    kDcsTermcapTerminfoRequestTerminfoName
+} DcsTermcapTerminfoRequestName;
+
 NS_INLINE BOOL isDCS(unsigned char *code, int len) {
     return (len >= 2 && code[0] == ESC && code[1] == 'P');
 }
@@ -22,5 +28,8 @@ NS_INLINE BOOL isDCS(unsigned char *code, int len) {
               token:(VT100Token *)result
            encoding:(NSStringEncoding)encoding;
 
++ (NSDictionary *)termcapTerminfoNameDictionary;  // string name -> DcsTermcapTerminfoRequestName
++ (NSDictionary *)termcapTerminfoInverseNameDictionary;  // DcsTermcapTerminfoRequestName -> string name
+
 @end
 

VT100DCSParser.m

@@ -20,7 +20,41 @@ + (void)decodeBytes:(unsigned char *)datap
     // Can assume we have "ESC P" so skip past that.
     datap += 2;
     datalen -= 2;
-    *rmlen=2;
+    *rmlen = 2;
+    if (datalen >= 2) {
+        if (!strncmp((char *)datap, "+q", 2)) {
+            datap += 2;
+            datalen -= 2;
+            *rmlen += 2;
+            char st[3] = { ESC, '\\', '\0' };
+            char *positionOfST = strnstr((const char *)datap, st, datalen);
+            if (!positionOfST) {
+                return;
+            }
+            int length = positionOfST - (char *)datap;
+            *rmlen += length + 2;
+            NSString *semicolonDelimitedHexEncodedNames =
+                [NSString stringWithFormat:@"%.*s", length, (char *)datap];
+            NSArray *hexEncodedNames =
+                [semicolonDelimitedHexEncodedNames componentsSeparatedByString:@";"];
+            result->type = DCS_REQUEST_TERMCAP_TERMINFO;
+            result.csi->count = 0;
+            NSDictionary *nameMap = [[self class] termcapTerminfoNameDictionary];
+            for (NSString *hexEncodedName in hexEncodedNames) {
+                NSString *name = [NSString stringWithHexEncodedString:hexEncodedName];
+                NSNumber *value = nameMap[name];
+                if (value) {
+                    result.csi->p[result.csi->count++] = [value intValue];
+                } else {
+                    result.csi->p[result.csi->count++] = kDcsTermcapTerminfoRequestUnrecognizedName;
+                }
+                if (result.csi->count == VT100CSIPARAM_MAX) {
+                    break;
+                }
+            }
+            return;
+        }
+    }
     if (datalen >= 5) {
         if (!strncmp((char *)datap, "1000p", 5)) {
             result->type = DCS_TMUX;
@@ -31,4 +65,20 @@ + (void)decodeBytes:(unsigned char *)datap
     }
 }
 
++ (NSDictionary *)termcapTerminfoNameDictionary {
+    return @{ @"TN": @(kDcsTermcapTerminfoRequestTerminalName),
+              @"name": @(kDcsTermcapTerminfoRequestTerminfoName) };
+}
+
++ (NSDictionary *)termcapTerminfoInverseNameDictionary {
+    NSMutableDictionary *result = [NSMutableDictionary dictionary];
+    NSDictionary *dict = [self termcapTerminfoNameDictionary];
+    for (NSString *key in dict) {
+        id value = dict[key];
+        result[value] = key;
+    }
+    return result;
+}
+
+
 @end

VT100Screen.m

@@ -18,6 +18,7 @@
 #import "iTermGrowlDelegate.h"
 #import "iTermPreferences.h"
 #import "iTermSelection.h"
+#import "VT100DCSParser.h"
 #import "VT100Token.h"
 
 #import <apr-1/apr_base64.h>

VT100Terminal.m

@@ -1,6 +1,7 @@
 #import "VT100Terminal.h"
 #import "DebugLogging.h"
 #import "NSColor+iTerm.h"
+#import "VT100DCSParser.h"
 #import "VT100Parser.h"
 #import <apr-1/apr_base64.h>  // for xterm's base64 decoding (paste64)
 #include <term.h>
@@ -1547,6 +1548,38 @@ - (void)executeToken:(VT100Token *)token {
             [self executeXtermSetRgb:token];
             break;
 
+        case DCS_REQUEST_TERMCAP_TERMINFO: {
+            static NSString *const kFormat = @"%@=%@";
+            BOOL ok = NO;
+            NSMutableArray *parts = [NSMutableArray array];
+            NSDictionary *inverseMap = [VT100DCSParser termcapTerminfoInverseNameDictionary];
+            for (int i = 0; i < token.csi->count; i++) {
+                NSString *stringKey = inverseMap[@(token.csi->p[i])];
+                NSString *hexEncodedKey = [stringKey hexEncodedString];
+                switch (token.csi->p[i]) {
+                    case kDcsTermcapTerminfoRequestTerminfoName:
+                        [parts addObject:[NSString stringWithFormat:kFormat,
+                                          hexEncodedKey,
+                                          [_termType hexEncodedString]]];
+                        ok = YES;
+                        break;
+                    case kDcsTermcapTerminfoRequestTerminalName:
+                        [parts addObject:[NSString stringWithFormat:kFormat,
+                                          hexEncodedKey,
+                                          [@"iTerm2" hexEncodedString]]];
+                        ok = YES;
+                        break;
+                    case kDcsTermcapTerminfoRequestUnrecognizedName:
+                        i = token.csi->count;
+                        break;
+                }
+            }
+            NSString *s = [NSString stringWithFormat:@"\033P%d+r%@\033\\",
+                           ok ? 1 : 0,
+                           [parts componentsJoinedByString:@";"]];
+            [delegate_ terminalSendReport:[s dataUsingEncoding:NSUTF8StringEncoding]];
+            break;
+        }
         default:
             NSLog(@"Unexpected token type %d", (int)token->type);
             break;

VT100Token.h

@@ -151,9 +151,12 @@ typedef enum {
     ANSICSI_SCP,     // Save cursor position
     ANSICSI_RCP,     // Restore cursor position
     ANSICSI_CBT,     // Back tab
-    
+
     ANSI_RIS,        // Reset to initial state (there's also a CSI version)
 
+    // DCS
+    DCS_REQUEST_TERMCAP_TERMINFO,  // Request Termcap/Terminfo String
+
     // Toggle between ansi/vt52
     STRICT_ANSI_MODE,
 

VT100Token.m

@@ -209,7 +209,8 @@ - (NSString *)codeName {
                           @(DCS_TMUX):                        @"DCS_TMUX",
                           @(TMUX_LINE):                       @"TMUX_LINE",
                           @(TMUX_EXIT):                       @"TMUX_EXIT",
-                          @(VT100CSI_DECSLRM_OR_ANSICSI_SCP): @"VT100CSI_DECSLRM_OR_ANSICSI_SCP" };
+                          @(VT100CSI_DECSLRM_OR_ANSICSI_SCP): @"VT100CSI_DECSLRM_OR_ANSICSI_SCP",
+                          @(DCS_REQUEST_TERMCAP_TERMINFO):    @"DCS_REQUEST_TERMCAP_TERMINFO", };
     NSString *name = map[@(type)];
     if (name) {
         return name;

tests/report_broken

@@ -0,0 +1 @@
+P+q\

tests/report_name_tn

@@ -0,0 +1 @@
+P+q6E616D65;544E\

tests/report_tn

@@ -0,0 +1 @@
+P+q544E\