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-rw-r--r--xdiff/xemit.c197
1 files changed, 197 insertions, 0 deletions
diff --git a/xdiff/xemit.c b/xdiff/xemit.c
new file mode 100644
index 0000000000..e291dc7608
--- /dev/null
+++ b/xdiff/xemit.c
@@ -0,0 +1,197 @@
+/*
+ * 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 xdchange_t *xdl_get_hunk(xdchange_t *xscr, xdemitconf_t const *xecfg);
+
+
+
+
+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.
+ */
+static xdchange_t *xdl_get_hunk(xdchange_t *xscr, xdemitconf_t const *xecfg) {
+ xdchange_t *xch, *xchp;
+
+ for (xchp = xscr, xch = xscr->next; xch; xchp = xch, xch = xch->next)
+ if (xch->i1 - (xchp->i1 + xchp->chg1) > 2 * xecfg->ctxlen)
+ break;
+
+ return xchp;
+}
+
+
+static void xdl_find_func(xdfile_t *xf, long i, char *buf, long sz, long *ll) {
+
+ /*
+ * 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;
+
+ *ll = 0;
+ while (i-- > 0) {
+ len = xdl_get_rec(xf, i, &rec);
+ if (len > 0 &&
+ (isalpha((unsigned char)*rec) || /* identifier? */
+ *rec == '_' || /* also identifier? */
+ *rec == '$')) { /* mysterious GNU diff's invention */
+ if (len > sz)
+ len = sz;
+ while (0 < len && isspace((unsigned char)rec[len - 1]))
+ len--;
+ memcpy(buf, rec, len);
+ *ll = len;
+ return;
+ }
+ }
+}
+
+
+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;
+
+ if (xecfg->flags & XDL_EMIT_COMMON)
+ return xdl_emit_common(xe, xscr, ecb, xecfg);
+
+ for (xch = xche = 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);
+ }
+ 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;
+}
+