lbuf.c

   1 #include <ctype.h>
   2 #include <stdlib.h>
   3 #include <stdio.h>
   4 #include <string.h>
   5 #include <unistd.h>
   6 #include "vi.h"
   7
   8 #define NMARKS_BASE             ('z' - 'a' + 2)
   9 #define NMARKS                  32
  10
  11 /* line operations */
  12 struct lopt {
  13         char *ins;              /* inserted text */
  14         char *del;              /* deleted text */
  15         int pos, n_ins, n_del;  /* modification location */
  16         int pos_off;            /* cursor line offset */
  17         int seq;                /* operation number */
  18         int *mark, *mark_off;   /* saved marks */
  19 };
  20
  21 /* line buffers */
  22 struct lbuf {
  23         int mark[NMARKS];       /* mark lines */
  24         int mark_off[NMARKS];   /* mark line offsets */
  25         char **ln;              /* buffer lines */
  26         int ln_n;               /* number of lines in ln[] */
  27         int ln_sz;              /* size of ln[] */
  28         int useq;               /* current operation sequence */
  29         struct lopt *hist;      /* buffer history */
  30         int hist_sz;            /* size of hist[] */
  31         int hist_n;             /* current history head in hist[] */
  32         int hist_u;             /* current undo head in hist[] */
  33         int useq_zero;          /* useq for lbuf_saved() */
  34         int useq_last;          /* useq before hist[] */
  35 };
  36
  37 struct lbuf *lbuf_make(void)
  38 {
  39         struct lbuf *lb = malloc(sizeof(*lb));
  40         int i;
  41         memset(lb, 0, sizeof(*lb));
  42         for (i = 0; i < LEN(lb->mark); i++)
  43                 lb->mark[i] = -1;
  44         lb->useq = 1;
  45         return lb;
  46 }
  47
  48 static void lopt_done(struct lopt *lo)
  49 {
  50         free(lo->ins);
  51         free(lo->del);
  52         free(lo->mark);
  53         free(lo->mark_off);
  54 }
  55
  56 static void lbuf_savemark(struct lbuf *lb, struct lopt *lo, int m)
  57 {
  58         if (lb->mark[m] >= 0) {
  59                 if (!lo->mark) {
  60                         lo->mark = malloc(sizeof(lb->mark));
  61                         lo->mark_off = malloc(sizeof(lb->mark_off));
  62                         memset(lo->mark, 0xff, sizeof(lb->mark));
  63                 }
  64                 lo->mark[m] = lb->mark[m];
  65                 lo->mark_off[m] = lb->mark_off[m];
  66         }
  67 }
  68
  69 static void lbuf_loadmark(struct lbuf *lb, struct lopt *lo, int m)
  70 {
  71         if (lo->mark && lo->mark[m] >= 0) {
  72                 lb->mark[m] = lo->mark[m];
  73                 lb->mark_off[m] = lo->mark_off[m];
  74         }
  75 }
  76
  77 static int markidx(int mark)
  78 {
  79         if (islower(mark))
  80                 return mark - 'a';
  81         if (mark == '\'' || mark == '`')
  82                 return 'z' - 'a' + 1;
  83         if (mark == '*')
  84                 return 'z' - 'a' + 2;
  85         if (mark == '[')
  86                 return 'z' - 'a' + 3;
  87         if (mark == ']')
  88                 return 'z' - 'a' + 4;
  89         return -1;
  90 }
  91
  92 static void lbuf_savepos(struct lbuf *lb, struct lopt *lo)
  93 {
  94         if (lb->mark[markidx('*')] >= 0)
  95                 lo->pos_off = lb->mark_off[markidx('*')];
  96 }
  97
  98 static void lbuf_loadpos(struct lbuf *lb, struct lopt *lo)
  99 {
 100         lb->mark[markidx('*')] = lo->pos;
 101         lb->mark_off[markidx('*')] = lo->pos_off;
 102 }
 103
 104 void lbuf_free(struct lbuf *lb)
 105 {
 106         int i;
 107         for (i = 0; i < lb->ln_n; i++)
 108                 free(lb->ln[i]);
 109         for (i = 0; i < lb->hist_n; i++)
 110                 lopt_done(&lb->hist[i]);
 111         free(lb->hist);
 112         free(lb->ln);
 113         free(lb);
 114 }
 115
 116 /* insert a line at pos */
 117 static void lbuf_insertline(struct lbuf *lb, int pos, char *s)
 118 {
 119         if (lb->ln_n == lb->ln_sz) {
 120                 int nsz = lb->ln_sz + 512;
 121                 char **nln = malloc(nsz * sizeof(nln[0]));
 122                 memcpy(nln, lb->ln, lb->ln_n * sizeof(lb->ln[0]));
 123                 free(lb->ln);
 124                 lb->ln = nln;
 125                 lb->ln_sz = nsz;
 126         }
 127         memmove(lb->ln + pos + 1, lb->ln + pos,
 128                 (lb->ln_n - pos) * sizeof(lb->ln[0]));
 129         lb->ln_n++;
 130         lb->ln[pos] = s;
 131 }
 132
 133 /* low-level replacement */
 134 static void lbuf_replace(struct lbuf *lb, char *s, int pos, int n_del)
 135 {
 136         char *r;
 137         int n_ins = 0;
 138         int i;
 139         for (i = 0; i < n_del; i++)
 140                 free(lb->ln[pos + i]);
 141         memmove(lb->ln + pos, lb->ln + pos + n_del,
 142                 (lb->ln_n - pos - n_del) * sizeof(lb->ln[0]));
 143         lb->ln_n -= n_del;
 144         while (s && (r = strchr(s, '\n'))) {
 145                 char *n = malloc(r - s + 2);
 146                 memcpy(n, s, r - s + 1);
 147                 n[r - s + 1] = '\0';
 148                 lbuf_insertline(lb, pos + n_ins++, n);
 149                 s = r + 1;
 150         }
 151         for (i = 0; i < LEN(lb->mark); i++) {   /* updating marks */
 152                 if (!s && lb->mark[i] >= pos && lb->mark[i] < pos + n_del)
 153                         lb->mark[i] = -1;
 154                 else if (lb->mark[i] >= pos + n_del)
 155                         lb->mark[i] += n_ins - n_del;
 156                 else if (lb->mark[i] >= pos + n_ins)
 157                         lb->mark[i] = pos + n_ins - 1;
 158         }
 159         lbuf_mark(lb, '[', pos, 0);
 160         lbuf_mark(lb, ']', pos + (n_ins ? n_ins - 1 : 0), 0);
 161 }
 162
 163 static int uc_newlines(char *s)
 164 {
 165         int n;
 166         for (n = 0; (s = strchr(s, '\n')); n++)
 167                 s++;
 168         return n;
 169 }
 170
 171 /* append undo/redo history */
 172 static void lbuf_opt(struct lbuf *lb, char *buf, int pos, int n_del)
 173 {
 174         struct lopt *lo;
 175         int i;
 176         for (i = lb->hist_u; i < lb->hist_n; i++)
 177                 lopt_done(&lb->hist[i]);
 178         lb->hist_n = lb->hist_u;
 179         if (lb->hist_n == lb->hist_sz) {
 180                 int sz = lb->hist_sz + 128;
 181                 struct lopt *hist = malloc(sz * sizeof(hist[0]));
 182                 memcpy(hist, lb->hist, lb->hist_n * sizeof(hist[0]));
 183                 free(lb->hist);
 184                 lb->hist = hist;
 185                 lb->hist_sz = sz;
 186         }
 187         lo = &lb->hist[lb->hist_n];
 188         lb->hist_n++;
 189         lb->hist_u = lb->hist_n;
 190         memset(lo, 0, sizeof(*lo));
 191         lo->pos = pos;
 192         lo->n_del = n_del;
 193         lo->del = n_del ? lbuf_cp(lb, pos, pos + n_del) : NULL;
 194         lo->n_ins = buf ? uc_newlines(buf) : 0;
 195         lo->ins = buf ? uc_dup(buf) : NULL;
 196         lo->seq = lb->useq;
 197         lbuf_savepos(lb, lo);
 198         for (i = 0; i < NMARKS_BASE; i++)
 199                 if (lb->mark[i] >= pos && lb->mark[i] < pos + n_del)
 200                         lbuf_savemark(lb, lo, i);
 201 }
 202
 203 void lbuf_rd(struct lbuf *lbuf, int fd, int beg, int end)
 204 {
 205         char buf[1 << 10];
 206         struct sbuf *sb;
 207         int nr;
 208         sb = sbuf_make();
 209         while ((nr = read(fd, buf, sizeof(buf))) > 0)
 210                 sbuf_mem(sb, buf, nr);
 211         lbuf_edit(lbuf, sbuf_buf(sb), beg, end);
 212         sbuf_free(sb);
 213 }
 214
 215 void lbuf_wr(struct lbuf *lbuf, int fd, int beg, int end)
 216 {
 217         int i;
 218         for (i = beg; i < end; i++)
 219                 write(fd, lbuf->ln[i], strlen(lbuf->ln[i]));
 220 }
 221
 222 /* replace lines beg through end with buf */
 223 void lbuf_edit(struct lbuf *lb, char *buf, int beg, int end)
 224 {
 225         if (beg > lb->ln_n)
 226                 beg = lb->ln_n;
 227         if (end > lb->ln_n)
 228                 end = lb->ln_n;
 229         if (beg == end && !buf)
 230                 return;
 231         lbuf_opt(lb, buf, beg, end - beg);
 232         lbuf_replace(lb, buf, beg, end - beg);
 233 }
 234
 235 char *lbuf_cp(struct lbuf *lb, int beg, int end)
 236 {
 237         struct sbuf *sb;
 238         int i;
 239         sb = sbuf_make();
 240         for (i = beg; i < end; i++)
 241                 if (i < lb->ln_n)
 242                         sbuf_str(sb, lb->ln[i]);
 243         return sbuf_done(sb);
 244 }
 245
 246 char *lbuf_get(struct lbuf *lb, int pos)
 247 {
 248         return pos >= 0 && pos < lb->ln_n ? lb->ln[pos] : NULL;
 249 }
 250
 251 int lbuf_len(struct lbuf *lb)
 252 {
 253         return lb->ln_n;
 254 }
 255
 256 void lbuf_mark(struct lbuf *lbuf, int mark, int pos, int off)
 257 {
 258         if (markidx(mark) >= 0) {
 259                 lbuf->mark[markidx(mark)] = pos;
 260                 lbuf->mark_off[markidx(mark)] = off;
 261         }
 262 }
 263
 264 int lbuf_jump(struct lbuf *lbuf, int mark, int *pos, int *off)
 265 {
 266         int mk = markidx(mark);
 267         if (mk < 0 || lbuf->mark[mk] < 0)
 268                 return 1;
 269         *pos = lbuf->mark[mk];
 270         if (off)
 271                 *off = lbuf->mark_off[mk];
 272         return 0;
 273 }
 274
 275 int lbuf_undo(struct lbuf *lb)
 276 {
 277         int useq, i;
 278         if (!lb->hist_u)
 279                 return 1;
 280         useq = lb->hist[lb->hist_u - 1].seq;
 281         while (lb->hist_u && lb->hist[lb->hist_u - 1].seq == useq) {
 282                 struct lopt *lo = &lb->hist[--(lb->hist_u)];
 283                 lbuf_replace(lb, lo->del, lo->pos, lo->n_ins);
 284                 lbuf_loadpos(lb, lo);
 285                 for (i = 0; i < LEN(lb->mark); i++)
 286                         lbuf_loadmark(lb, lo, i);
 287         }
 288         return 0;
 289 }
 290
 291 int lbuf_redo(struct lbuf *lb)
 292 {
 293         int useq;
 294         if (lb->hist_u == lb->hist_n)
 295                 return 1;
 296         useq = lb->hist[lb->hist_u].seq;
 297         while (lb->hist_u < lb->hist_n && lb->hist[lb->hist_u].seq == useq) {
 298                 struct lopt *lo = &lb->hist[lb->hist_u++];
 299                 lbuf_replace(lb, lo->ins, lo->pos, lo->n_del);
 300                 lbuf_loadpos(lb, lo);
 301         }
 302         return 0;
 303 }
 304
 305 static int lbuf_seq(struct lbuf *lb)
 306 {
 307         return lb->hist_u ? lb->hist[lb->hist_u - 1].seq : lb->useq_last;
 308 }
 309
 310 /* mark buffer as saved and, if clear, clear the undo history */
 311 void lbuf_saved(struct lbuf *lb, int clear)
 312 {
 313         int i;
 314         if (clear) {
 315                 for (i = 0; i < lb->hist_n; i++)
 316                         lopt_done(&lb->hist[i]);
 317                 lb->hist_n = 0;
 318                 lb->hist_u = 0;
 319                 lb->useq_last = lb->useq;
 320         }
 321         lb->useq_zero = lbuf_seq(lb);
 322         lbuf_modified(xb);
 323 }
 324
 325 /* was the file modified since the last lbuf_modreset() */
 326 int lbuf_modified(struct lbuf *lb)
 327 {
 328         lb->useq++;
 329         return lbuf_seq(lb) != lb->useq_zero;
 330 }