1 /* $OpenBSD: ex_shift.c,v 1.7 2014/11/12 04:28:41 bentley Exp $ */ 2 3 /*- 4 * Copyright (c) 1992, 1993, 1994 5 * The Regents of the University of California. All rights reserved. 6 * Copyright (c) 1992, 1993, 1994, 1995, 1996 7 * Keith Bostic. All rights reserved. 8 * 9 * See the LICENSE file for redistribution information. 10 */ 11 12 #include "config.h" 13 14 #include <sys/queue.h> 15 16 #include <bitstring.h> 17 #include <limits.h> 18 #include <stdio.h> 19 #include <stdlib.h> 20 #include <string.h> 21 22 #include "../common/common.h" 23 24 enum which {LEFT, RIGHT}; 25 static int shift(SCR *, EXCMD *, enum which); 26 27 /* 28 * ex_shiftl -- :<[<...] 29 * 30 * 31 * PUBLIC: int ex_shiftl(SCR *, EXCMD *); 32 */ 33 int 34 ex_shiftl(SCR *sp, EXCMD *cmdp) 35 { 36 return (shift(sp, cmdp, LEFT)); 37 } 38 39 /* 40 * ex_shiftr -- :>[>...] 41 * 42 * PUBLIC: int ex_shiftr(SCR *, EXCMD *); 43 */ 44 int 45 ex_shiftr(SCR *sp, EXCMD *cmdp) 46 { 47 return (shift(sp, cmdp, RIGHT)); 48 } 49 50 /* 51 * shift -- 52 * Ex shift support. 53 */ 54 static int 55 shift(SCR *sp, EXCMD *cmdp, enum which rl) 56 { 57 recno_t from, to; 58 size_t blen, len, newcol, newidx, oldcol, oldidx, sw; 59 int curset; 60 char *p, *bp, *tbp; 61 62 NEEDFILE(sp, cmdp); 63 64 if (O_VAL(sp, O_SHIFTWIDTH) == 0) { 65 msgq(sp, M_INFO, "152|shiftwidth option set to 0"); 66 return (0); 67 } 68 69 /* Copy the lines being shifted into the unnamed buffer. */ 70 if (cut(sp, NULL, &cmdp->addr1, &cmdp->addr2, CUT_LINEMODE)) 71 return (1); 72 73 /* 74 * The historic version of vi permitted the user to string any number 75 * of '>' or '<' characters together, resulting in an indent of the 76 * appropriate levels. There's a special hack in ex_cmd() so that 77 * cmdp->argv[0] points to the string of '>' or '<' characters. 78 * 79 * Q: What's the difference between the people adding features 80 * to vi and the Girl Scouts? 81 * A: The Girl Scouts have mint cookies and adult supervision. 82 */ 83 for (p = cmdp->argv[0]->bp, sw = 0; *p == '>' || *p == '<'; ++p) 84 sw += O_VAL(sp, O_SHIFTWIDTH); 85 86 GET_SPACE_RET(sp, bp, blen, 256); 87 88 curset = 0; 89 for (from = cmdp->addr1.lno, to = cmdp->addr2.lno; from <= to; ++from) { 90 if (db_get(sp, from, DBG_FATAL, &p, &len)) 91 goto err; 92 if (!len) { 93 if (sp->lno == from) 94 curset = 1; 95 continue; 96 } 97 98 /* 99 * Calculate the old indent amount and the number of 100 * characters it used. 101 */ 102 for (oldidx = 0, oldcol = 0; oldidx < len; ++oldidx) 103 if (p[oldidx] == ' ') 104 ++oldcol; 105 else if (p[oldidx] == '\t') 106 oldcol += O_VAL(sp, O_TABSTOP) - 107 oldcol % O_VAL(sp, O_TABSTOP); 108 else 109 break; 110 111 /* Calculate the new indent amount. */ 112 if (rl == RIGHT) 113 newcol = oldcol + sw; 114 else { 115 newcol = oldcol < sw ? 0 : oldcol - sw; 116 if (newcol == oldcol) { 117 if (sp->lno == from) 118 curset = 1; 119 continue; 120 } 121 } 122 123 /* Get a buffer that will hold the new line. */ 124 ADD_SPACE_RET(sp, bp, blen, newcol + len); 125 126 /* 127 * Build a new indent string and count the number of 128 * characters it uses. 129 */ 130 for (tbp = bp, newidx = 0; 131 newcol >= O_VAL(sp, O_TABSTOP); ++newidx) { 132 *tbp++ = '\t'; 133 newcol -= O_VAL(sp, O_TABSTOP); 134 } 135 for (; newcol > 0; --newcol, ++newidx) 136 *tbp++ = ' '; 137 138 /* Add the original line. */ 139 memcpy(tbp, p + oldidx, len - oldidx); 140 141 /* Set the replacement line. */ 142 if (db_set(sp, from, bp, (tbp + (len - oldidx)) - bp)) { 143 err: FREE_SPACE(sp, bp, blen); 144 return (1); 145 } 146 147 /* 148 * !!! 149 * The shift command in historic vi had the usual bizarre 150 * collection of cursor semantics. If called from vi, the 151 * cursor was repositioned to the first non-blank character 152 * of the lowest numbered line shifted. If called from ex, 153 * the cursor was repositioned to the first non-blank of the 154 * highest numbered line shifted. Here, if the cursor isn't 155 * part of the set of lines that are moved, move it to the 156 * first non-blank of the last line shifted. (This makes 157 * ":3>>" in vi work reasonably.) If the cursor is part of 158 * the shifted lines, it doesn't get moved at all. This 159 * permits shifting of marked areas, i.e. ">'a." shifts the 160 * marked area twice, something that couldn't be done with 161 * historic vi. 162 */ 163 if (sp->lno == from) { 164 curset = 1; 165 if (newidx > oldidx) 166 sp->cno += newidx - oldidx; 167 else if (sp->cno >= oldidx - newidx) 168 sp->cno -= oldidx - newidx; 169 } 170 } 171 if (!curset) { 172 sp->lno = to; 173 sp->cno = 0; 174 (void)nonblank(sp, to, &sp->cno); 175 } 176 177 FREE_SPACE(sp, bp, blen); 178 179 sp->rptlines[L_SHIFT] += cmdp->addr2.lno - cmdp->addr1.lno + 1; 180 return (0); 181 } 182