Usermode/Libraries/libreadline.so_src/main.c

   1 /*
   2  * Acess2 Library Suite
   3  * - Readline
   4  *
   5  * Text mode entry with history
   6  */
   7 #include <readline.h>
   8 #include <acess/sys.h>
   9 #include <stdlib.h>
  10 #include <stdio.h>
  11 #include <string.h>
  12
  13 #define STDIN_FD        0
  14 #define STDOUT_FD       1
  15
  16 // === PROTOTYPES ===
  17  int    SoMain();
  18 tReadline       *Readline_CreateInstance(int bUseHistory);
  19 char    *Readline(tReadline *Info);
  20
  21 // === GLOBALS ===
  22
  23 // === CODE ===
  24 int SoMain()
  25 {
  26         return 0;
  27 }
  28
  29 char *Readline(tReadline *Info)
  30 {
  31         char    *ret;
  32         char    *orig;
  33          int    len, pos, space = 1023-8-8;     // optimised for the heap manager
  34         char    ch;
  35          int    scrollbackPos = Info->NumHistory;
  36
  37         // Preset Variables
  38         ret = malloc( space+1 );
  39         if(!ret)        return NULL;
  40         len = 0;        pos = 0;
  41
  42         orig = ret;
  43
  44         // Read In Command Line
  45         do {
  46                 read(STDIN_FD, 1, &ch); // Read Character from stdin (read is a blocking call)
  47
  48                 if(ch == '\n')  break;
  49
  50                 switch(ch)
  51                 {
  52                 // Control characters
  53                 case '\x1B':
  54                         read(STDIN_FD, 1, &ch); // Read control character
  55                         switch(ch)
  56                         {
  57                         //case 'D':     if(pos) pos--;  break;
  58                         //case 'C':     if(pos<len)     pos++;  break;
  59                         case '[':
  60                                 read(STDIN_FD, 1, &ch); // Read control character
  61                                 switch(ch)
  62                                 {
  63                                 case 'A':       // Up
  64                                         {
  65                                                  int    oldLen = len;
  66                                                 if( scrollbackPos <= 0 )        break;
  67
  68                                                 if(ret != orig) free(ret);
  69                                                 ret = strdup( Info->History[--scrollbackPos] );
  70
  71                                                 space = len = strlen(ret);
  72                                                 while(pos-->1)  write(STDOUT_FD, 3, "\x1B[D");
  73                                                 write(STDOUT_FD, len, ret);     pos = len;
  74                                                 while(pos++ < oldLen)   write(STDOUT_FD, 1, " ");
  75                                         }
  76                                         break;
  77                                 case 'B':       // Down
  78                                         {
  79                                                  int    oldLen = len;
  80                                                 if( scrollbackPos >= Info->NumHistory ) break;
  81
  82                                                 if(ret != orig) free(ret);
  83                                                 ret = strdup( Info->History[scrollbackPos++] );
  84
  85                                                 space = len = strlen(ret);
  86                                                 while(pos-->1)  write(STDOUT_FD, 3, "\x1B[D");
  87                                                 write(STDOUT_FD, len, ret);     pos = len;
  88                                                 while(pos++ < oldLen)   write(STDOUT_FD, 1, " ");
  89                                         }
  90                                         break;
  91                                 case 'D':       // Left
  92                                         if(pos == 0)    break;
  93                                         pos --;
  94                                         write(STDOUT_FD, 3, "\x1B[D");
  95                                         break;
  96                                 case 'C':       // Right
  97                                         if(pos == len)  break;
  98                                         pos++;
  99                                         write(STDOUT_FD, 3, "\x1B[C");
 100                                         break;
 101                                 }
 102                         }
 103                         break;
 104
 105                 // Backspace
 106                 case '\b':
 107                         if(len <= 0)            break;  // Protect against underflows
 108                         write(STDOUT_FD, 1, &ch);
 109                         if(pos == len) {        // Simple case of end of string
 110                                 len --;
 111                                 pos--;
 112                         }
 113                         else {
 114                                 char    buf[7] = "\x1B[000D";
 115                                 buf[2] += ((len-pos+1)/100) % 10;
 116                                 buf[3] += ((len-pos+1)/10) % 10;
 117                                 buf[4] += (len-pos+1) % 10;
 118                                 write(STDOUT_FD, len-pos, &ret[pos]);   // Move Text
 119                                 ch = ' ';       write(STDOUT_FD, 1, &ch);       ch = '\b';      // Clear deleted character
 120                                 write(STDOUT_FD, 7, buf);       // Update Cursor
 121                                 // Alter Buffer
 122                                 memmove(&ret[pos-1], &ret[pos], len-pos);
 123                                 pos --;
 124                                 len --;
 125                         }
 126                         break;
 127
 128                 // Tab
 129                 case '\t':
 130                         //TODO: Implement Tab-Completion
 131                         //Currently just ignore tabs
 132                         break;
 133
 134                 default:
 135                         // Expand Buffer
 136                         if(len+1 > space) {
 137                                 space += 256;
 138                                 if(ret == orig) {
 139                                         orig = ret = realloc(ret, space+1);
 140                                 }
 141                                 else {
 142                                         ret = realloc(ret, space+1);
 143                                 }
 144                                 if(!ret)        return NULL;
 145                         }
 146
 147                         // Editing inside the buffer
 148                         if(pos != len) {
 149                                 char    buf[7] = "\x1B[000D";
 150                                 buf[2] += ((len-pos)/100) % 10;
 151                                 buf[3] += ((len-pos)/10) % 10;
 152                                 buf[4] += (len-pos) % 10;
 153                                 write(STDOUT_FD, 1, &ch);       // Print new character
 154                                 write(STDOUT_FD, len-pos, &ret[pos]);   // Move Text
 155                                 write(STDOUT_FD, 7, buf);       // Update Cursor
 156                                 memmove( &ret[pos+1], &ret[pos], len-pos );
 157                         }
 158                         else {
 159                                 write(STDOUT_FD, 1, &ch);
 160                         }
 161                         ret[pos++] = ch;
 162                         len ++;
 163                         break;
 164                 }
 165         } while(ch != '\n');
 166
 167         // Cap String
 168         ret[len] = '\0';
 169         printf("\n");
 170
 171         // Return length
 172         //if(Length)    *Length = len;
 173
 174         // Add to history
 175         if( Info->UseHistory )
 176         {
 177                 if( !Info->History || strcmp( Info->History[ Info->NumHistory-1 ], ret) != 0 )
 178                 {
 179                         void    *tmp;
 180                         Info->NumHistory ++;
 181                         tmp = realloc( Info->History, Info->NumHistory * sizeof(char*) );
 182                         if(tmp != NULL)
 183                         {
 184                                 Info->History = tmp;
 185                                 Info->History[ Info->NumHistory-1 ] = strdup(ret);
 186                         }
 187                 }
 188         }
 189
 190         if(ret != orig) free(orig);
 191
 192         return ret;
 193 }