diff options
Diffstat (limited to 'xdiff/xemit.c')
| -rw-r--r-- | xdiff/xemit.c | 205 |
1 files changed, 205 insertions, 0 deletions
diff --git a/xdiff/xemit.c b/xdiff/xemit.c new file mode 100644 index 0000000..c4bedf0 --- /dev/null +++ b/xdiff/xemit.c @@ -0,0 +1,205 @@ +/* + * LibXDiff by Davide Libenzi ( File Differential Library ) + * Copyright (C) 2003 Davide Libenzi + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; either + * version 2.1 of the License, or (at your option) any later version. + * + * This library is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with this library; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + * + * Davide Libenzi <davidel@xmailserver.org> + * + */ + +#include "xinclude.h" + + + + +static long xdl_get_rec(xdfile_t *xdf, long ri, char const **rec); +static int xdl_emit_record(xdfile_t *xdf, long ri, char const *pre, xdemitcb_t *ecb); + + + + +static long xdl_get_rec(xdfile_t *xdf, long ri, char const **rec) { + + *rec = xdf->recs[ri]->ptr; + + return xdf->recs[ri]->size; +} + + +static int xdl_emit_record(xdfile_t *xdf, long ri, char const *pre, xdemitcb_t *ecb) { + long size, psize = strlen(pre); + char const *rec; + + size = xdl_get_rec(xdf, ri, &rec); + if (xdl_emit_diffrec(rec, size, pre, psize, ecb) < 0) { + + return -1; + } + + return 0; +} + + +/* + * Starting at the passed change atom, find the latest change atom to be included + * inside the differential hunk according to the specified configuration. + */ +xdchange_t *xdl_get_hunk(xdchange_t *xscr, xdemitconf_t const *xecfg) { + xdchange_t *xch, *xchp; + long max_common = 2 * xecfg->ctxlen + xecfg->interhunkctxlen; + + for (xchp = xscr, xch = xscr->next; xch; xchp = xch, xch = xch->next) + if (xch->i1 - (xchp->i1 + xchp->chg1) > max_common) + break; + + return xchp; +} + + +static long def_ff(const char *rec, long len, char *buf, long sz, void *priv) +{ + if (len > 0 && + (isalpha((unsigned char)*rec) || /* identifier? */ + *rec == '_' || /* also identifier? */ + *rec == '$')) { /* identifiers from VMS and other esoterico */ + if (len > sz) + len = sz; + while (0 < len && isspace((unsigned char)rec[len - 1])) + len--; + memcpy(buf, rec, len); + return len; + } + return -1; +} + +static void xdl_find_func(xdfile_t *xf, long i, char *buf, long sz, long *ll, + find_func_t ff, void *ff_priv) { + + /* + * Be quite stupid about this for now. Find a line in the old file + * before the start of the hunk (and context) which starts with a + * plausible character. + */ + + const char *rec; + long len; + + while (i-- > 0) { + len = xdl_get_rec(xf, i, &rec); + if ((*ll = ff(rec, len, buf, sz, ff_priv)) >= 0) + return; + } + *ll = 0; +} + + +static int xdl_emit_common(xdfenv_t *xe, xdchange_t *xscr, xdemitcb_t *ecb, + xdemitconf_t const *xecfg) { + xdfile_t *xdf = &xe->xdf1; + const char *rchg = xdf->rchg; + long ix; + + for (ix = 0; ix < xdf->nrec; ix++) { + if (rchg[ix]) + continue; + if (xdl_emit_record(xdf, ix, "", ecb)) + return -1; + } + return 0; +} + +int xdl_emit_diff(xdfenv_t *xe, xdchange_t *xscr, xdemitcb_t *ecb, + xdemitconf_t const *xecfg) { + long s1, s2, e1, e2, lctx; + xdchange_t *xch, *xche; + char funcbuf[80]; + long funclen = 0; + find_func_t ff = xecfg->find_func ? xecfg->find_func : def_ff; + + if (xecfg->flags & XDL_EMIT_COMMON) + return xdl_emit_common(xe, xscr, ecb, xecfg); + + for (xch = xscr; xch; xch = xche->next) { + xche = xdl_get_hunk(xch, xecfg); + + s1 = XDL_MAX(xch->i1 - xecfg->ctxlen, 0); + s2 = XDL_MAX(xch->i2 - xecfg->ctxlen, 0); + + lctx = xecfg->ctxlen; + lctx = XDL_MIN(lctx, xe->xdf1.nrec - (xche->i1 + xche->chg1)); + lctx = XDL_MIN(lctx, xe->xdf2.nrec - (xche->i2 + xche->chg2)); + + e1 = xche->i1 + xche->chg1 + lctx; + e2 = xche->i2 + xche->chg2 + lctx; + + /* + * Emit current hunk header. + */ + + if (xecfg->flags & XDL_EMIT_FUNCNAMES) { + xdl_find_func(&xe->xdf1, s1, funcbuf, + sizeof(funcbuf), &funclen, + ff, xecfg->find_func_priv); + } + if (xdl_emit_hunk_hdr(s1 + 1, e1 - s1, s2 + 1, e2 - s2, + funcbuf, funclen, ecb) < 0) + return -1; + + /* + * Emit pre-context. + */ + for (; s1 < xch->i1; s1++) + if (xdl_emit_record(&xe->xdf1, s1, " ", ecb) < 0) + return -1; + + for (s1 = xch->i1, s2 = xch->i2;; xch = xch->next) { + /* + * Merge previous with current change atom. + */ + for (; s1 < xch->i1 && s2 < xch->i2; s1++, s2++) + if (xdl_emit_record(&xe->xdf1, s1, " ", ecb) < 0) + return -1; + + /* + * Removes lines from the first file. + */ + for (s1 = xch->i1; s1 < xch->i1 + xch->chg1; s1++) + if (xdl_emit_record(&xe->xdf1, s1, "-", ecb) < 0) + return -1; + + /* + * Adds lines from the second file. + */ + for (s2 = xch->i2; s2 < xch->i2 + xch->chg2; s2++) + if (xdl_emit_record(&xe->xdf2, s2, "+", ecb) < 0) + return -1; + + if (xch == xche) + break; + s1 = xch->i1 + xch->chg1; + s2 = xch->i2 + xch->chg2; + } + + /* + * Emit post-context. + */ + for (s1 = xche->i1 + xche->chg1; s1 < e1; s1++) + if (xdl_emit_record(&xe->xdf1, s1, " ", ecb) < 0) + return -1; + } + + return 0; +} |