Andrew's git - gitweb.git/blob

   1/*
   2 *  LibXDiff by Davide Libenzi ( File Differential Library )
   3 *  Copyright (C) 2003  Davide Libenzi
   4 *
   5 *  This library is free software; you can redistribute it and/or
   6 *  modify it under the terms of the GNU Lesser General Public
   7 *  License as published by the Free Software Foundation; either
   8 *  version 2.1 of the License, or (at your option) any later version.
   9 *
  10 *  This library is distributed in the hope that it will be useful,
  11 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13 *  Lesser General Public License for more details.
  14 *
  15 *  You should have received a copy of the GNU Lesser General Public
  16 *  License along with this library; if not, write to the Free Software
  17 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  18 *
  19 *  Davide Libenzi <davidel@xmailserver.org>
  20 *
  21 */
  22
  23#include "xinclude.h"
  24
  25
  26
  27#define XDL_GUESS_NLINES 256
  28
  29
  30
  31
  32long xdl_bogosqrt(long n) {
  33        long i;
  34
  35        /*
  36         * Classical integer square root approximation using shifts.
  37         */
  38        for (i = 1; n > 0; n >>= 2)
  39                i <<= 1;
  40
  41        return i;
  42}
  43
  44
  45int xdl_emit_diffrec(char const *rec, long size, char const *pre, long psize,
  46                     xdemitcb_t *ecb) {
  47        int i = 2;
  48        mmbuffer_t mb[3];
  49
  50        mb[0].ptr = (char *) pre;
  51        mb[0].size = psize;
  52        mb[1].ptr = (char *) rec;
  53        mb[1].size = size;
  54        if (size > 0 && rec[size - 1] != '\n') {
  55                mb[2].ptr = (char *) "\n\\ No newline at end of file\n";
  56                mb[2].size = strlen(mb[2].ptr);
  57                i++;
  58        }
  59        if (ecb->outf(ecb->priv, mb, i) < 0) {
  60
  61                return -1;
  62        }
  63
  64        return 0;
  65}
  66
  67void *xdl_mmfile_first(mmfile_t *mmf, long *size)
  68{
  69        *size = mmf->size;
  70        return mmf->ptr;
  71}
  72
  73
  74void *xdl_mmfile_next(mmfile_t *mmf, long *size)
  75{
  76        return NULL;
  77}
  78
  79
  80long xdl_mmfile_size(mmfile_t *mmf)
  81{
  82        return mmf->size;
  83}
  84
  85
  86int xdl_cha_init(chastore_t *cha, long isize, long icount) {
  87
  88        cha->head = cha->tail = NULL;
  89        cha->isize = isize;
  90        cha->nsize = icount * isize;
  91        cha->ancur = cha->sncur = NULL;
  92        cha->scurr = 0;
  93
  94        return 0;
  95}
  96
  97
  98void xdl_cha_free(chastore_t *cha) {
  99        chanode_t *cur, *tmp;
 100
 101        for (cur = cha->head; (tmp = cur) != NULL;) {
 102                cur = cur->next;
 103                xdl_free(tmp);
 104        }
 105}
 106
 107
 108void *xdl_cha_alloc(chastore_t *cha) {
 109        chanode_t *ancur;
 110        void *data;
 111
 112        if (!(ancur = cha->ancur) || ancur->icurr == cha->nsize) {
 113                if (!(ancur = (chanode_t *) xdl_malloc(sizeof(chanode_t) + cha->nsize))) {
 114
 115                        return NULL;
 116                }
 117                ancur->icurr = 0;
 118                ancur->next = NULL;
 119                if (cha->tail)
 120                        cha->tail->next = ancur;
 121                if (!cha->head)
 122                        cha->head = ancur;
 123                cha->tail = ancur;
 124                cha->ancur = ancur;
 125        }
 126
 127        data = (char *) ancur + sizeof(chanode_t) + ancur->icurr;
 128        ancur->icurr += cha->isize;
 129
 130        return data;
 131}
 132
 133
 134void *xdl_cha_first(chastore_t *cha) {
 135        chanode_t *sncur;
 136
 137        if (!(cha->sncur = sncur = cha->head))
 138                return NULL;
 139
 140        cha->scurr = 0;
 141
 142        return (char *) sncur + sizeof(chanode_t) + cha->scurr;
 143}
 144
 145
 146void *xdl_cha_next(chastore_t *cha) {
 147        chanode_t *sncur;
 148
 149        if (!(sncur = cha->sncur))
 150                return NULL;
 151        cha->scurr += cha->isize;
 152        if (cha->scurr == sncur->icurr) {
 153                if (!(sncur = cha->sncur = sncur->next))
 154                        return NULL;
 155                cha->scurr = 0;
 156        }
 157
 158        return (char *) sncur + sizeof(chanode_t) + cha->scurr;
 159}
 160
 161
 162long xdl_guess_lines(mmfile_t *mf) {
 163        long nl = 0, size, tsize = 0;
 164        char const *data, *cur, *top;
 165
 166        if ((cur = data = xdl_mmfile_first(mf, &size)) != NULL) {
 167                for (top = data + size; nl < XDL_GUESS_NLINES;) {
 168                        if (cur >= top) {
 169                                tsize += (long) (cur - data);
 170                                if (!(cur = data = xdl_mmfile_next(mf, &size)))
 171                                        break;
 172                                top = data + size;
 173                        }
 174                        nl++;
 175                        if (!(cur = memchr(cur, '\n', top - cur)))
 176                                cur = top;
 177                        else
 178                                cur++;
 179                }
 180                tsize += (long) (cur - data);
 181        }
 182
 183        if (nl && tsize)
 184                nl = xdl_mmfile_size(mf) / (tsize / nl);
 185
 186        return nl + 1;
 187}
 188
 189int xdl_recmatch(const char *l1, long s1, const char *l2, long s2, long flags)
 190{
 191        int i1, i2;
 192
 193        if (flags & XDF_IGNORE_WHITESPACE) {
 194                for (i1 = i2 = 0; i1 < s1 && i2 < s2; i1++, i2++) {
 195                        if (isspace(l1[i1]))
 196                                while (isspace(l1[i1]) && i1 < s1)
 197                                        i1++;
 198                        else if (isspace(l2[i2]))
 199                                while (isspace(l2[i2]) && i2 < s2)
 200                                        i2++;
 201                        else if (l1[i1] != l2[i2])
 202                                return l2[i2] - l1[i1];
 203                }
 204                if (i1 >= s1)
 205                        return 1;
 206                else if (i2 >= s2)
 207                        return -1;
 208        } else if (flags & XDF_IGNORE_WHITESPACE_CHANGE) {
 209                for (i1 = i2 = 0; i1 < s1 && i2 < s2; i1++, i2++) {
 210                        if (isspace(l1[i1])) {
 211                                if (!isspace(l2[i2]))
 212                                        return -1;
 213                                while (isspace(l1[i1]) && i1 < s1)
 214                                        i1++;
 215                                while (isspace(l2[i2]) && i2 < s2)
 216                                        i2++;
 217                        } else if (l1[i1] != l2[i2])
 218                                return l2[i2] - l1[i1];
 219                }
 220                if (i1 >= s1)
 221                        return 1;
 222                else if (i2 >= s2)
 223                        return -1;
 224        } else
 225                return s1 == s2 && !memcmp(l1, l2, s1);
 226
 227        return 0;
 228}
 229
 230unsigned long xdl_hash_record(char const **data, char const *top, long flags) {
 231        unsigned long ha = 5381;
 232        char const *ptr = *data;
 233
 234        for (; ptr < top && *ptr != '\n'; ptr++) {
 235                if (isspace(*ptr) && (flags & XDF_WHITESPACE_FLAGS)) {
 236                        while (ptr < top && isspace(*ptr) && ptr[1] != '\n')
 237                                ptr++;
 238                        if (flags & XDF_IGNORE_WHITESPACE_CHANGE) {
 239                                ha += (ha << 5);
 240                                ha ^= (unsigned long) ' ';
 241                        }
 242                        continue;
 243                }
 244                ha += (ha << 5);
 245                ha ^= (unsigned long) *ptr;
 246        }
 247        *data = ptr < top ? ptr + 1: ptr;
 248
 249        return ha;
 250}
 251
 252
 253unsigned int xdl_hashbits(unsigned int size) {
 254        unsigned int val = 1, bits = 0;
 255
 256        for (; val < size && bits < CHAR_BIT * sizeof(unsigned int); val <<= 1, bits++);
 257        return bits ? bits: 1;
 258}
 259
 260
 261int xdl_num_out(char *out, long val) {
 262        char *ptr, *str = out;
 263        char buf[32];
 264
 265        ptr = buf + sizeof(buf) - 1;
 266        *ptr = '\0';
 267        if (val < 0) {
 268                *--ptr = '-';
 269                val = -val;
 270        }
 271        for (; val && ptr > buf; val /= 10)
 272                *--ptr = "0123456789"[val % 10];
 273        if (*ptr)
 274                for (; *ptr; ptr++, str++)
 275                        *str = *ptr;
 276        else
 277                *str++ = '0';
 278        *str = '\0';
 279
 280        return str - out;
 281}
 282
 283
 284long xdl_atol(char const *str, char const **next) {
 285        long val, base;
 286        char const *top;
 287
 288        for (top = str; XDL_ISDIGIT(*top); top++);
 289        if (next)
 290                *next = top;
 291        for (val = 0, base = 1, top--; top >= str; top--, base *= 10)
 292                val += base * (long)(*top - '0');
 293        return val;
 294}
 295
 296
 297int xdl_emit_hunk_hdr(long s1, long c1, long s2, long c2,
 298                      const char *func, long funclen, xdemitcb_t *ecb) {
 299        int nb = 0;
 300        mmbuffer_t mb;
 301        char buf[128];
 302
 303        memcpy(buf, "@@ -", 4);
 304        nb += 4;
 305
 306        nb += xdl_num_out(buf + nb, c1 ? s1: s1 - 1);
 307
 308        if (c1 != 1) {
 309                memcpy(buf + nb, ",", 1);
 310                nb += 1;
 311
 312                nb += xdl_num_out(buf + nb, c1);
 313        }
 314
 315        memcpy(buf + nb, " +", 2);
 316        nb += 2;
 317
 318        nb += xdl_num_out(buf + nb, c2 ? s2: s2 - 1);
 319
 320        if (c2 != 1) {
 321                memcpy(buf + nb, ",", 1);
 322                nb += 1;
 323
 324                nb += xdl_num_out(buf + nb, c2);
 325        }
 326
 327        memcpy(buf + nb, " @@", 3);
 328        nb += 3;
 329        if (func && funclen) {
 330                buf[nb++] = ' ';
 331                if (funclen > sizeof(buf) - nb - 1)
 332                        funclen = sizeof(buf) - nb - 1;
 333                memcpy(buf + nb, func, funclen);
 334                nb += funclen;
 335        }
 336        buf[nb++] = '\n';
 337
 338        mb.ptr = buf;
 339        mb.size = nb;
 340        if (ecb->outf(ecb->priv, &mb, 1) < 0)
 341                return -1;
 342
 343        return 0;
 344}
 345