1 /*- 2 * Copyright (c) 1992, 1993, 1994 3 * The Regents of the University of California. All rights reserved. 4 * Copyright (c) 1992, 1993, 1994, 1995, 1996 5 * Keith Bostic. All rights reserved. 6 * 7 * See the LICENSE file for redistribution information. 8 */ 9 10 #include "config.h" 11 12 #ifndef lint 13 static const char sccsid[] = "$Id: delete.c,v 10.18 2012/02/11 15:52:33 zy Exp $"; 14 #endif /* not lint */ 15 16 #include <sys/types.h> 17 #include <sys/queue.h> 18 #include <sys/time.h> 19 20 #include <bitstring.h> 21 #include <errno.h> 22 #include <limits.h> 23 #include <stdio.h> 24 #include <stdlib.h> 25 #include <string.h> 26 27 #include "common.h" 28 29 /* 30 * del -- 31 * Delete a range of text. 32 * 33 * PUBLIC: int del(SCR *, MARK *, MARK *, int); 34 */ 35 int 36 del( 37 SCR *sp, 38 MARK *fm, 39 MARK *tm, 40 int lmode) 41 { 42 recno_t lno; 43 size_t blen, len, nlen, tlen; 44 CHAR_T *bp, *p; 45 int eof, rval; 46 47 bp = NULL; 48 49 /* Case 1 -- delete in line mode. */ 50 if (lmode) { 51 for (lno = tm->lno; lno >= fm->lno; --lno) { 52 if (db_delete(sp, lno)) 53 return (1); 54 ++sp->rptlines[L_DELETED]; 55 if (lno % INTERRUPT_CHECK == 0 && INTERRUPTED(sp)) 56 break; 57 } 58 goto done; 59 } 60 61 /* 62 * Case 2 -- delete to EOF. This is a special case because it's 63 * easier to pick it off than try and find it in the other cases. 64 */ 65 if (db_last(sp, &lno)) 66 return (1); 67 if (tm->lno >= lno) { 68 if (tm->lno == lno) { 69 if (db_get(sp, lno, DBG_FATAL, &p, &len)) 70 return (1); 71 eof = tm->cno != ENTIRE_LINE && tm->cno >= len ? 1 : 0; 72 } else 73 eof = 1; 74 if (eof) { 75 for (lno = tm->lno; lno > fm->lno; --lno) { 76 if (db_delete(sp, lno)) 77 return (1); 78 ++sp->rptlines[L_DELETED]; 79 if (lno % 80 INTERRUPT_CHECK == 0 && INTERRUPTED(sp)) 81 break; 82 } 83 if (db_get(sp, fm->lno, DBG_FATAL, &p, &len)) 84 return (1); 85 GET_SPACE_RETW(sp, bp, blen, fm->cno); 86 MEMCPY(bp, p, fm->cno); 87 if (db_set(sp, fm->lno, bp, fm->cno)) 88 return (1); 89 goto done; 90 } 91 } 92 93 /* Case 3 -- delete within a single line. */ 94 if (tm->lno == fm->lno) { 95 if (db_get(sp, fm->lno, DBG_FATAL, &p, &len)) 96 return (1); 97 GET_SPACE_RETW(sp, bp, blen, len); 98 if (fm->cno != 0) 99 MEMCPY(bp, p, fm->cno); 100 MEMCPY(bp + fm->cno, p + (tm->cno + 1), 101 len - (tm->cno + 1)); 102 if (db_set(sp, fm->lno, 103 bp, len - ((tm->cno - fm->cno) + 1))) 104 goto err; 105 goto done; 106 } 107 108 /* 109 * Case 4 -- delete over multiple lines. 110 * 111 * Copy the start partial line into place. 112 */ 113 if ((tlen = fm->cno) != 0) { 114 if (db_get(sp, fm->lno, DBG_FATAL, &p, NULL)) 115 return (1); 116 GET_SPACE_RETW(sp, bp, blen, tlen + 256); 117 MEMCPY(bp, p, tlen); 118 } 119 120 /* Copy the end partial line into place. */ 121 if (db_get(sp, tm->lno, DBG_FATAL, &p, &len)) 122 goto err; 123 if (len != 0 && tm->cno != len - 1) { 124 /* 125 * XXX 126 * We can overflow memory here, if the total length is greater 127 * than SIZE_T_MAX. The only portable way I've found to test 128 * is depending on the overflow being less than the value. 129 */ 130 nlen = (len - (tm->cno + 1)) + tlen; 131 if (tlen > nlen) { 132 msgq(sp, M_ERR, "002|Line length overflow"); 133 goto err; 134 } 135 if (tlen == 0) { 136 GET_SPACE_RETW(sp, bp, blen, nlen); 137 } else 138 ADD_SPACE_RETW(sp, bp, blen, nlen); 139 140 MEMCPY(bp + tlen, p + (tm->cno + 1), len - (tm->cno + 1)); 141 tlen += len - (tm->cno + 1); 142 } 143 144 /* Set the current line. */ 145 if (db_set(sp, fm->lno, bp, tlen)) 146 goto err; 147 148 /* Delete the last and intermediate lines. */ 149 for (lno = tm->lno; lno > fm->lno; --lno) { 150 if (db_delete(sp, lno)) 151 goto err; 152 ++sp->rptlines[L_DELETED]; 153 if (lno % INTERRUPT_CHECK == 0 && INTERRUPTED(sp)) 154 break; 155 } 156 157 done: rval = 0; 158 if (0) 159 err: rval = 1; 160 if (bp != NULL) 161 FREE_SPACEW(sp, bp, blen); 162 return (rval); 163 } 164