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[] = "@(#)delete.c 10.12 (Berkeley) 10/23/96"; 14 #endif /* not lint */ 15 16 #include <sys/types.h> 17 #include <sys/queue.h> 18 19 #include <bitstring.h> 20 #include <errno.h> 21 #include <limits.h> 22 #include <stdio.h> 23 #include <stdlib.h> 24 #include <string.h> 25 26 #include "common.h" 27 28 /* 29 * del -- 30 * Delete a range of text. 31 * 32 * PUBLIC: int del __P((SCR *, MARK *, MARK *, int)); 33 */ 34 int 35 del(sp, fm, tm, lmode) 36 SCR *sp; 37 MARK *fm, *tm; 38 int lmode; 39 { 40 recno_t lno; 41 size_t blen, len, nlen, tlen; 42 char *bp, *p; 43 int eof, rval; 44 45 bp = NULL; 46 47 /* Case 1 -- delete in line mode. */ 48 if (lmode) { 49 for (lno = tm->lno; lno >= fm->lno; --lno) { 50 if (db_delete(sp, lno)) 51 return (1); 52 ++sp->rptlines[L_DELETED]; 53 if (lno % INTERRUPT_CHECK == 0 && INTERRUPTED(sp)) 54 break; 55 } 56 goto done; 57 } 58 59 /* 60 * Case 2 -- delete to EOF. This is a special case because it's 61 * easier to pick it off than try and find it in the other cases. 62 */ 63 if (db_last(sp, &lno)) 64 return (1); 65 if (tm->lno >= lno) { 66 if (tm->lno == lno) { 67 if (db_get(sp, lno, DBG_FATAL, &p, &len)) 68 return (1); 69 eof = tm->cno >= len ? 1 : 0; 70 } else 71 eof = 1; 72 if (eof) { 73 for (lno = tm->lno; lno > fm->lno; --lno) { 74 if (db_delete(sp, lno)) 75 return (1); 76 ++sp->rptlines[L_DELETED]; 77 if (lno % 78 INTERRUPT_CHECK == 0 && INTERRUPTED(sp)) 79 break; 80 } 81 if (db_get(sp, fm->lno, DBG_FATAL, &p, &len)) 82 return (1); 83 GET_SPACE_RET(sp, bp, blen, fm->cno); 84 memcpy(bp, p, fm->cno); 85 if (db_set(sp, fm->lno, bp, fm->cno)) 86 return (1); 87 goto done; 88 } 89 } 90 91 /* Case 3 -- delete within a single line. */ 92 if (tm->lno == fm->lno) { 93 if (db_get(sp, fm->lno, DBG_FATAL, &p, &len)) 94 return (1); 95 GET_SPACE_RET(sp, bp, blen, len); 96 if (fm->cno != 0) 97 memcpy(bp, p, fm->cno); 98 memcpy(bp + fm->cno, p + (tm->cno + 1), len - (tm->cno + 1)); 99 if (db_set(sp, fm->lno, 100 bp, len - ((tm->cno - fm->cno) + 1))) 101 goto err; 102 goto done; 103 } 104 105 /* 106 * Case 4 -- delete over multiple lines. 107 * 108 * Copy the start partial line into place. 109 */ 110 if ((tlen = fm->cno) != 0) { 111 if (db_get(sp, fm->lno, DBG_FATAL, &p, NULL)) 112 return (1); 113 GET_SPACE_RET(sp, bp, blen, tlen + 256); 114 memcpy(bp, p, tlen); 115 } 116 117 /* Copy the end partial line into place. */ 118 if (db_get(sp, tm->lno, DBG_FATAL, &p, &len)) 119 goto err; 120 if (len != 0 && tm->cno != len - 1) { 121 /* 122 * XXX 123 * We can overflow memory here, if the total length is greater 124 * than SIZE_T_MAX. The only portable way I've found to test 125 * is depending on the overflow being less than the value. 126 */ 127 nlen = (len - (tm->cno + 1)) + tlen; 128 if (tlen > nlen) { 129 msgq(sp, M_ERR, "002|Line length overflow"); 130 goto err; 131 } 132 if (tlen == 0) { 133 GET_SPACE_RET(sp, bp, blen, nlen); 134 } else 135 ADD_SPACE_RET(sp, bp, blen, nlen); 136 137 memcpy(bp + tlen, p + (tm->cno + 1), len - (tm->cno + 1)); 138 tlen += len - (tm->cno + 1); 139 } 140 141 /* Set the current line. */ 142 if (db_set(sp, fm->lno, bp, tlen)) 143 goto err; 144 145 /* Delete the last and intermediate lines. */ 146 for (lno = tm->lno; lno > fm->lno; --lno) { 147 if (db_delete(sp, lno)) 148 goto err; 149 ++sp->rptlines[L_DELETED]; 150 if (lno % INTERRUPT_CHECK == 0 && INTERRUPTED(sp)) 151 break; 152 } 153 154 done: rval = 0; 155 if (0) 156 err: rval = 1; 157 if (bp != NULL) 158 FREE_SPACE(sp, bp, blen); 159 return (rval); 160 } 161