/* $OpenBSD: diffreg.c,v 1.93 2019/06/28 13:35:00 deraadt Exp $ */ /*- * SPDX-License-Identifier: BSD-4-Clause * * Copyright (C) Caldera International Inc. 2001-2002. * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code and documentation must retain the above * copyright notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed or owned by Caldera * International, Inc. * 4. Neither the name of Caldera International, Inc. nor the names of other * contributors may be used to endorse or promote products derived from * this software without specific prior written permission. * * USE OF THE SOFTWARE PROVIDED FOR UNDER THIS LICENSE BY CALDERA * INTERNATIONAL, INC. AND CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. * IN NO EVENT SHALL CALDERA INTERNATIONAL, INC. BE LIABLE FOR ANY DIRECT, * INDIRECT INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. */ /*- * Copyright (c) 1991, 1993 * The Regents of the University of California. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "pr.h" #include "diff.h" #include "xmalloc.h" /* * diff - compare two files. */ /* * Uses an algorithm due to Harold Stone, which finds a pair of longest * identical subsequences in the two files. * * The major goal is to generate the match vector J. J[i] is the index of * the line in file1 corresponding to line i file0. J[i] = 0 if there is no * such line in file1. * * Lines are hashed so as to work in core. All potential matches are * located by sorting the lines of each file on the hash (called * ``value''). In particular, this collects the equivalence classes in * file1 together. Subroutine equiv replaces the value of each line in * file0 by the index of the first element of its matching equivalence in * (the reordered) file1. To save space equiv squeezes file1 into a single * array member in which the equivalence classes are simply concatenated, * except that their first members are flagged by changing sign. * * Next the indices that point into member are unsorted into array class * according to the original order of file0. * * The cleverness lies in routine stone. This marches through the lines of * file0, developing a vector klist of "k-candidates". At step i * a k-candidate is a matched pair of lines x,y (x in file0 y in file1) * such that there is a common subsequence of length k between the first * i lines of file0 and the first y lines of file1, but there is no such * subsequence for any smaller y. x is the earliest possible mate to y that * occurs in such a subsequence. * * Whenever any of the members of the equivalence class of lines in file1 * matable to a line in file0 has serial number less than the y of some * k-candidate, that k-candidate with the smallest such y is replaced. The * new k-candidate is chained (via pred) to the current k-1 candidate so * that the actual subsequence can be recovered. When a member has serial * number greater that the y of all k-candidates, the klist is extended. At * the end, the longest subsequence is pulled out and placed in the array J * by unravel. * * With J in hand, the matches there recorded are check'ed against reality * to assure that no spurious matches have crept in due to hashing. If they * have, they are broken, and "jackpot" is recorded -- a harmless matter * except that a true match for a spuriously mated line may now be * unnecessarily reported as a change. * * Much of the complexity of the program comes simply from trying to * minimize core utilization and maximize the range of doable problems by * dynamically allocating what is needed and reusing what is not. The core * requirements for problems larger than somewhat are (in words) * 2*length(file0) + length(file1) + 3*(number of k-candidates installed), * typically about 6n words for files of length n. */ struct cand { int x; int y; int pred; }; static struct line { int serial; int value; } *file[2]; /* * The following struct is used to record change information when * doing a "context" or "unified" diff. (see routine "change" to * understand the highly mnemonic field names) */ struct context_vec { int a; /* start line in old file */ int b; /* end line in old file */ int c; /* start line in new file */ int d; /* end line in new file */ }; enum readhash { RH_BINARY, RH_OK, RH_EOF }; #define MIN_PAD 1 static FILE *opentemp(const char *); static void output(char *, FILE *, char *, FILE *, int); static void check(FILE *, FILE *, int); static void range(int, int, const char *); static void uni_range(int, int); static void dump_context_vec(FILE *, FILE *, int); static void dump_unified_vec(FILE *, FILE *, int); static bool prepare(int, FILE *, size_t, int); static void prune(void); static void equiv(struct line *, int, struct line *, int, int *); static void unravel(int); static void unsort(struct line *, int, int *); static void change(char *, FILE *, char *, FILE *, int, int, int, int, int *); static void sort(struct line *, int); static void print_header(const char *, const char *); static void print_space(int, int, int); static bool ignoreline_pattern(char *); static bool ignoreline(char *, bool); static int asciifile(FILE *); static int fetch(long *, int, int, FILE *, int, int, int); static int newcand(int, int, int); static int search(int *, int, int); static int skipline(FILE *); static int stone(int *, int, int *, int *, int); static enum readhash readhash(FILE *, int, unsigned *); static int files_differ(FILE *, FILE *, int); static char *match_function(const long *, int, FILE *); static char *preadline(int, size_t, off_t); static int *J; /* will be overlaid on class */ static int *class; /* will be overlaid on file[0] */ static int *klist; /* will be overlaid on file[0] after class */ static int *member; /* will be overlaid on file[1] */ static int clen; static int inifdef; /* whether or not we are in a #ifdef block */ static int len[2]; static int pref, suff; /* length of prefix and suffix */ static int slen[2]; static int anychange; static int hw, padding; /* half width and padding */ static int edoffset; static long *ixnew; /* will be overlaid on file[1] */ static long *ixold; /* will be overlaid on klist */ static struct cand *clist; /* merely a free storage pot for candidates */ static int clistlen; /* the length of clist */ static struct line *sfile[2]; /* shortened by pruning common prefix/suffix */ static int (*chrtran)(int); /* translation table for case-folding */ static struct context_vec *context_vec_start; static struct context_vec *context_vec_end; static struct context_vec *context_vec_ptr; #define FUNCTION_CONTEXT_SIZE 55 static char lastbuf[FUNCTION_CONTEXT_SIZE]; static int lastline; static int lastmatchline; static int clow2low(int c) { return (c); } static int cup2low(int c) { return (tolower(c)); } int diffreg(char *file1, char *file2, int flags, int capsicum) { FILE *f1, *f2; int i, rval; struct pr *pr = NULL; cap_rights_t rights_ro; f1 = f2 = NULL; rval = D_SAME; anychange = 0; lastline = 0; lastmatchline = 0; /* * hw excludes padding and make sure when -t is not used, * the second column always starts from the closest tab stop */ if (diff_format == D_SIDEBYSIDE) { hw = width >> 1; padding = tabsize - (hw % tabsize); if ((flags & D_EXPANDTABS) != 0 || (padding % tabsize == 0)) padding = MIN_PAD; hw = (width >> 1) - ((padding == MIN_PAD) ? (padding << 1) : padding) - 1; } if (flags & D_IGNORECASE) chrtran = cup2low; else chrtran = clow2low; if (S_ISDIR(stb1.st_mode) != S_ISDIR(stb2.st_mode)) return (S_ISDIR(stb1.st_mode) ? D_MISMATCH1 : D_MISMATCH2); if (strcmp(file1, "-") == 0 && strcmp(file2, "-") == 0) goto closem; if (flags & D_EMPTY1) f1 = fopen(_PATH_DEVNULL, "r"); else { if (!S_ISREG(stb1.st_mode)) { if ((f1 = opentemp(file1)) == NULL || fstat(fileno(f1), &stb1) == -1) { warn("%s", file1); rval = D_ERROR; status |= 2; goto closem; } } else if (strcmp(file1, "-") == 0) f1 = stdin; else f1 = fopen(file1, "r"); } if (f1 == NULL) { warn("%s", file1); rval = D_ERROR; status |= 2; goto closem; } if (flags & D_EMPTY2) f2 = fopen(_PATH_DEVNULL, "r"); else { if (!S_ISREG(stb2.st_mode)) { if ((f2 = opentemp(file2)) == NULL || fstat(fileno(f2), &stb2) == -1) { warn("%s", file2); rval = D_ERROR; status |= 2; goto closem; } } else if (strcmp(file2, "-") == 0) f2 = stdin; else f2 = fopen(file2, "r"); } if (f2 == NULL) { warn("%s", file2); rval = D_ERROR; status |= 2; goto closem; } if (lflag) pr = start_pr(file1, file2); if (capsicum) { cap_rights_init(&rights_ro, CAP_READ, CAP_FSTAT, CAP_SEEK); if (caph_rights_limit(fileno(f1), &rights_ro) < 0) err(2, "unable to limit rights on: %s", file1); if (caph_rights_limit(fileno(f2), &rights_ro) < 0) err(2, "unable to limit rights on: %s", file2); if (fileno(f1) == STDIN_FILENO || fileno(f2) == STDIN_FILENO) { /* stdin has already been limited */ if (caph_limit_stderr() == -1) err(2, "unable to limit stderr"); if (caph_limit_stdout() == -1) err(2, "unable to limit stdout"); } else if (caph_limit_stdio() == -1) err(2, "unable to limit stdio"); caph_cache_catpages(); caph_cache_tzdata(); if (caph_enter() < 0) err(2, "unable to enter capability mode"); } switch (files_differ(f1, f2, flags)) { case 0: goto closem; case 1: break; default: /* error */ rval = D_ERROR; status |= 2; goto closem; } if (diff_format == D_BRIEF && ignore_pats == NULL && (flags & (D_FOLDBLANKS|D_IGNOREBLANKS|D_IGNORECASE|D_STRIPCR)) == 0) { rval = D_DIFFER; status |= 1; goto closem; } if ((flags & D_FORCEASCII) != 0) { (void)prepare(0, f1, stb1.st_size, flags); (void)prepare(1, f2, stb2.st_size, flags); } else if (!asciifile(f1) || !asciifile(f2) || !prepare(0, f1, stb1.st_size, flags) || !prepare(1, f2, stb2.st_size, flags)) { rval = D_BINARY; status |= 1; goto closem; } prune(); sort(sfile[0], slen[0]); sort(sfile[1], slen[1]); member = (int *)file[1]; equiv(sfile[0], slen[0], sfile[1], slen[1], member); member = xreallocarray(member, slen[1] + 2, sizeof(*member)); class = (int *)file[0]; unsort(sfile[0], slen[0], class); class = xreallocarray(class, slen[0] + 2, sizeof(*class)); klist = xcalloc(slen[0] + 2, sizeof(*klist)); clen = 0; clistlen = 100; clist = xcalloc(clistlen, sizeof(*clist)); i = stone(class, slen[0], member, klist, flags); free(member); free(class); J = xreallocarray(J, len[0] + 2, sizeof(*J)); unravel(klist[i]); free(clist); free(klist); ixold = xreallocarray(ixold, len[0] + 2, sizeof(*ixold)); ixnew = xreallocarray(ixnew, len[1] + 2, sizeof(*ixnew)); check(f1, f2, flags); output(file1, f1, file2, f2, flags); closem: if (pr != NULL) stop_pr(pr); if (anychange) { status |= 1; if (rval == D_SAME) rval = D_DIFFER; } if (f1 != NULL) fclose(f1); if (f2 != NULL) fclose(f2); return (rval); } /* * Check to see if the given files differ. * Returns 0 if they are the same, 1 if different, and -1 on error. * XXX - could use code from cmp(1) [faster] */ static int files_differ(FILE *f1, FILE *f2, int flags) { char buf1[BUFSIZ], buf2[BUFSIZ]; size_t i, j; if ((flags & (D_EMPTY1|D_EMPTY2)) || stb1.st_size != stb2.st_size || (stb1.st_mode & S_IFMT) != (stb2.st_mode & S_IFMT)) return (1); if (stb1.st_dev == stb2.st_dev && stb1.st_ino == stb2.st_ino) return (0); for (;;) { i = fread(buf1, 1, sizeof(buf1), f1); j = fread(buf2, 1, sizeof(buf2), f2); if ((!i && ferror(f1)) || (!j && ferror(f2))) return (-1); if (i != j) return (1); if (i == 0) return (0); if (memcmp(buf1, buf2, i) != 0) return (1); } } static FILE * opentemp(const char *f) { char buf[BUFSIZ], tempfile[PATH_MAX]; ssize_t nread; int ifd, ofd; if (strcmp(f, "-") == 0) ifd = STDIN_FILENO; else if ((ifd = open(f, O_RDONLY, 0644)) == -1) return (NULL); (void)strlcpy(tempfile, _PATH_TMP "/diff.XXXXXXXX", sizeof(tempfile)); if ((ofd = mkstemp(tempfile)) == -1) { close(ifd); return (NULL); } unlink(tempfile); while ((nread = read(ifd, buf, BUFSIZ)) > 0) { if (write(ofd, buf, nread) != nread) { close(ifd); close(ofd); return (NULL); } } close(ifd); lseek(ofd, (off_t)0, SEEK_SET); return (fdopen(ofd, "r")); } static bool prepare(int i, FILE *fd, size_t filesize, int flags) { struct line *p; unsigned h; size_t sz, j = 0; enum readhash r; rewind(fd); sz = MIN(filesize, SIZE_MAX) / 25; if (sz < 100) sz = 100; p = xcalloc(sz + 3, sizeof(*p)); while ((r = readhash(fd, flags, &h)) != RH_EOF) switch (r) { case RH_EOF: /* otherwise clang complains */ case RH_BINARY: return (false); case RH_OK: if (j == sz) { sz = sz * 3 / 2; p = xreallocarray(p, sz + 3, sizeof(*p)); } p[++j].value = h; } len[i] = j; file[i] = p; return (true); } static void prune(void) { int i, j; for (pref = 0; pref < len[0] && pref < len[1] && file[0][pref + 1].value == file[1][pref + 1].value; pref++) ; for (suff = 0; suff < len[0] - pref && suff < len[1] - pref && file[0][len[0] - suff].value == file[1][len[1] - suff].value; suff++) ; for (j = 0; j < 2; j++) { sfile[j] = file[j] + pref; slen[j] = len[j] - pref - suff; for (i = 0; i <= slen[j]; i++) sfile[j][i].serial = i; } } static void equiv(struct line *a, int n, struct line *b, int m, int *c) { int i, j; i = j = 1; while (i <= n && j <= m) { if (a[i].value < b[j].value) a[i++].value = 0; else if (a[i].value == b[j].value) a[i++].value = j; else j++; } while (i <= n) a[i++].value = 0; b[m + 1].value = 0; j = 0; while (++j <= m) { c[j] = -b[j].serial; while (b[j + 1].value == b[j].value) { j++; c[j] = b[j].serial; } } c[j] = -1; } static int stone(int *a, int n, int *b, int *c, int flags) { int i, k, y, j, l; int oldc, tc, oldl, sq; unsigned numtries, bound; if (flags & D_MINIMAL) bound = UINT_MAX; else { sq = sqrt(n); bound = MAX(256, sq); } k = 0; c[0] = newcand(0, 0, 0); for (i = 1; i <= n; i++) { j = a[i]; if (j == 0) continue; y = -b[j]; oldl = 0; oldc = c[0]; numtries = 0; do { if (y <= clist[oldc].y) continue; l = search(c, k, y); if (l != oldl + 1) oldc = c[l - 1]; if (l <= k) { if (clist[c[l]].y <= y) continue; tc = c[l]; c[l] = newcand(i, y, oldc); oldc = tc; oldl = l; numtries++; } else { c[l] = newcand(i, y, oldc); k++; break; } } while ((y = b[++j]) > 0 && numtries < bound); } return (k); } static int newcand(int x, int y, int pred) { struct cand *q; if (clen == clistlen) { clistlen = clistlen * 11 / 10; clist = xreallocarray(clist, clistlen, sizeof(*clist)); } q = clist + clen; q->x = x; q->y = y; q->pred = pred; return (clen++); } static int search(int *c, int k, int y) { int i, j, l, t; if (clist[c[k]].y < y) /* quick look for typical case */ return (k + 1); i = 0; j = k + 1; for (;;) { l = (i + j) / 2; if (l <= i) break; t = clist[c[l]].y; if (t > y) j = l; else if (t < y) i = l; else return (l); } return (l + 1); } static void unravel(int p) { struct cand *q; int i; for (i = 0; i <= len[0]; i++) J[i] = i <= pref ? i : i > len[0] - suff ? i + len[1] - len[0] : 0; for (q = clist + p; q->y != 0; q = clist + q->pred) J[q->x + pref] = q->y + pref; } /* * Check does double duty: * 1. ferret out any fortuitous correspondences due to confounding by * hashing (which result in "jackpot") * 2. collect random access indexes to the two files */ static void check(FILE *f1, FILE *f2, int flags) { int i, j, /* jackpot, */ c, d; long ctold, ctnew; rewind(f1); rewind(f2); j = 1; ixold[0] = ixnew[0] = 0; /* jackpot = 0; */ ctold = ctnew = 0; for (i = 1; i <= len[0]; i++) { if (J[i] == 0) { ixold[i] = ctold += skipline(f1); continue; } while (j < J[i]) { ixnew[j] = ctnew += skipline(f2); j++; } if (flags & (D_FOLDBLANKS | D_IGNOREBLANKS | D_IGNORECASE | D_STRIPCR)) { for (;;) { c = getc(f1); d = getc(f2); /* * GNU diff ignores a missing newline * in one file for -b or -w. */ if (flags & (D_FOLDBLANKS | D_IGNOREBLANKS)) { if (c == EOF && d == '\n') { ctnew++; break; } else if (c == '\n' && d == EOF) { ctold++; break; } } ctold++; ctnew++; if (flags & D_STRIPCR && (c == '\r' || d == '\r')) { if (c == '\r') { if ((c = getc(f1)) == '\n') { ctold++; } else { ungetc(c, f1); } } if (d == '\r') { if ((d = getc(f2)) == '\n') { ctnew++; } else { ungetc(d, f2); } } break; } if ((flags & D_FOLDBLANKS) && isspace(c) && isspace(d)) { do { if (c == '\n') break; ctold++; } while (isspace(c = getc(f1))); do { if (d == '\n') break; ctnew++; } while (isspace(d = getc(f2))); } else if (flags & D_IGNOREBLANKS) { while (isspace(c) && c != '\n') { c = getc(f1); ctold++; } while (isspace(d) && d != '\n') { d = getc(f2); ctnew++; } } if (chrtran(c) != chrtran(d)) { /* jackpot++; */ J[i] = 0; if (c != '\n' && c != EOF) ctold += skipline(f1); if (d != '\n' && c != EOF) ctnew += skipline(f2); break; } if (c == '\n' || c == EOF) break; } } else { for (;;) { ctold++; ctnew++; if ((c = getc(f1)) != (d = getc(f2))) { /* jackpot++; */ J[i] = 0; if (c != '\n' && c != EOF) ctold += skipline(f1); if (d != '\n' && c != EOF) ctnew += skipline(f2); break; } if (c == '\n' || c == EOF) break; } } ixold[i] = ctold; ixnew[j] = ctnew; j++; } for (; j <= len[1]; j++) { ixnew[j] = ctnew += skipline(f2); } /* * if (jackpot) * fprintf(stderr, "jackpot\n"); */ } /* shellsort CACM #201 */ static void sort(struct line *a, int n) { struct line *ai, *aim, w; int j, m = 0, k; if (n == 0) return; for (j = 1; j <= n; j *= 2) m = 2 * j - 1; for (m /= 2; m != 0; m /= 2) { k = n - m; for (j = 1; j <= k; j++) { for (ai = &a[j]; ai > a; ai -= m) { aim = &ai[m]; if (aim < ai) break; /* wraparound */ if (aim->value > ai[0].value || (aim->value == ai[0].value && aim->serial > ai[0].serial)) break; w.value = ai[0].value; ai[0].value = aim->value; aim->value = w.value; w.serial = ai[0].serial; ai[0].serial = aim->serial; aim->serial = w.serial; } } } } static void unsort(struct line *f, int l, int *b) { int *a, i; a = xcalloc(l + 1, sizeof(*a)); for (i = 1; i <= l; i++) a[f[i].serial] = f[i].value; for (i = 1; i <= l; i++) b[i] = a[i]; free(a); } static int skipline(FILE *f) { int i, c; for (i = 1; (c = getc(f)) != '\n' && c != EOF; i++) continue; return (i); } static void output(char *file1, FILE *f1, char *file2, FILE *f2, int flags) { int i, j, m, i0, i1, j0, j1, nc; rewind(f1); rewind(f2); m = len[0]; J[0] = 0; J[m + 1] = len[1] + 1; if (diff_format != D_EDIT) { for (i0 = 1; i0 <= m; i0 = i1 + 1) { while (i0 <= m && J[i0] == J[i0 - 1] + 1) { if (diff_format == D_SIDEBYSIDE && suppress_common != 1) { nc = fetch(ixold, i0, i0, f1, '\0', 1, flags); print_space(nc, (hw - nc) + (padding << 1) + 1, flags); fetch(ixnew, J[i0], J[i0], f2, '\0', 0, flags); printf("\n"); } i0++; } j0 = J[i0 - 1] + 1; i1 = i0 - 1; while (i1 < m && J[i1 + 1] == 0) i1++; j1 = J[i1 + 1] - 1; J[i1] = j1; /* * When using side-by-side, lines from both of the files are * printed. The algorithm used by diff(1) identifies the ranges * in which two files differ. * See the change() function below. * The for loop below consumes the shorter range, whereas one of * the while loops deals with the longer one. */ if (diff_format == D_SIDEBYSIDE) { for (i = i0, j = j0; i <= i1 && j <= j1; i++, j++) change(file1, f1, file2, f2, i, i, j, j, &flags); while (i <= i1) { change(file1, f1, file2, f2, i, i, j + 1, j, &flags); i++; } while (j <= j1) { change(file1, f1, file2, f2, i + 1, i, j, j, &flags); j++; } } else change(file1, f1, file2, f2, i0, i1, j0, j1, &flags); } } else { for (i0 = m; i0 >= 1; i0 = i1 - 1) { while (i0 >= 1 && J[i0] == J[i0 + 1] - 1 && J[i0] != 0) i0--; j0 = J[i0 + 1] - 1; i1 = i0 + 1; while (i1 > 1 && J[i1 - 1] == 0) i1--; j1 = J[i1 - 1] + 1; J[i1] = j1; change(file1, f1, file2, f2, i1, i0, j1, j0, &flags); } } if (m == 0) change(file1, f1, file2, f2, 1, 0, 1, len[1], &flags); if (diff_format == D_IFDEF || diff_format == D_GFORMAT) { for (;;) { #define c i0 if ((c = getc(f1)) == EOF) return; printf("%c", c); } #undef c } if (anychange != 0) { if (diff_format == D_CONTEXT) dump_context_vec(f1, f2, flags); else if (diff_format == D_UNIFIED) dump_unified_vec(f1, f2, flags); } } static void range(int a, int b, const char *separator) { printf("%d", a > b ? b : a); if (a < b) printf("%s%d", separator, b); } static void uni_range(int a, int b) { if (a < b) printf("%d,%d", a, b - a + 1); else if (a == b) printf("%d", b); else printf("%d,0", b); } static char * preadline(int fd, size_t rlen, off_t off) { char *line; ssize_t nr; line = xmalloc(rlen + 1); if ((nr = pread(fd, line, rlen, off)) == -1) err(2, "preadline"); if (nr > 0 && line[nr-1] == '\n') nr--; line[nr] = '\0'; return (line); } static bool ignoreline_pattern(char *line) { int ret; ret = regexec(&ignore_re, line, 0, NULL, 0); return (ret == 0); /* if it matched, it should be ignored. */ } static bool ignoreline(char *line, bool skip_blanks) { if (skip_blanks && *line == '\0') return (true); if (ignore_pats != NULL && ignoreline_pattern(line)) return (true); return (false); } /* * Indicate that there is a difference between lines a and b of the from file * to get to lines c to d of the to file. If a is greater then b then there * are no lines in the from file involved and this means that there were * lines appended (beginning at b). If c is greater than d then there are * lines missing from the to file. */ static void change(char *file1, FILE *f1, char *file2, FILE *f2, int a, int b, int c, int d, int *pflags) { static size_t max_context = 64; long curpos; int i, nc; const char *walk; bool skip_blanks, ignore; skip_blanks = (*pflags & D_SKIPBLANKLINES); restart: if ((diff_format != D_IFDEF || diff_format == D_GFORMAT) && a > b && c > d) return; if (ignore_pats != NULL || skip_blanks) { char *line; /* * All lines in the change, insert, or delete must match an ignore * pattern for the change to be ignored. */ if (a <= b) { /* Changes and deletes. */ for (i = a; i <= b; i++) { line = preadline(fileno(f1), ixold[i] - ixold[i - 1], ixold[i - 1]); ignore = ignoreline(line, skip_blanks); free(line); if (!ignore) goto proceed; } } if (a > b || c <= d) { /* Changes and inserts. */ for (i = c; i <= d; i++) { line = preadline(fileno(f2), ixnew[i] - ixnew[i - 1], ixnew[i - 1]); ignore = ignoreline(line, skip_blanks); free(line); if (!ignore) goto proceed; } } return; } proceed: if (*pflags & D_HEADER && diff_format != D_BRIEF) { printf("%s %s %s\n", diffargs, file1, file2); *pflags &= ~D_HEADER; } if (diff_format == D_CONTEXT || diff_format == D_UNIFIED) { /* * Allocate change records as needed. */ if (context_vec_start == NULL || context_vec_ptr == context_vec_end - 1) { ptrdiff_t offset = -1; if (context_vec_start != NULL) offset = context_vec_ptr - context_vec_start; max_context <<= 1; context_vec_start = xreallocarray(context_vec_start, max_context, sizeof(*context_vec_start)); context_vec_end = context_vec_start + max_context; context_vec_ptr = context_vec_start + offset; } if (anychange == 0) { /* * Print the context/unidiff header first time through. */ print_header(file1, file2); anychange = 1; } else if (a > context_vec_ptr->b + (2 * diff_context) + 1 && c > context_vec_ptr->d + (2 * diff_context) + 1) { /* * If this change is more than 'diff_context' lines from the * previous change, dump the record and reset it. */ if (diff_format == D_CONTEXT) dump_context_vec(f1, f2, *pflags); else dump_unified_vec(f1, f2, *pflags); } context_vec_ptr++; context_vec_ptr->a = a; context_vec_ptr->b = b; context_vec_ptr->c = c; context_vec_ptr->d = d; return; } if (anychange == 0) anychange = 1; switch (diff_format) { case D_BRIEF: return; case D_NORMAL: case D_EDIT: range(a, b, ","); printf("%c", a > b ? 'a' : c > d ? 'd' : 'c'); if (diff_format == D_NORMAL) range(c, d, ","); printf("\n"); break; case D_REVERSE: printf("%c", a > b ? 'a' : c > d ? 'd' : 'c'); range(a, b, " "); printf("\n"); break; case D_NREVERSE: if (a > b) printf("a%d %d\n", b, d - c + 1); else { printf("d%d %d\n", a, b - a + 1); if (!(c > d)) /* add changed lines */ printf("a%d %d\n", b, d - c + 1); } break; } if (diff_format == D_GFORMAT) { curpos = ftell(f1); /* print through if append (a>b), else to (nb: 0 vs 1 orig) */ nc = ixold[a > b ? b : a - 1] - curpos; for (i = 0; i < nc; i++) printf("%c", getc(f1)); for (walk = group_format; *walk != '\0'; walk++) { if (*walk == '%') { walk++; switch (*walk) { case '<': fetch(ixold, a, b, f1, '<', 1, *pflags); break; case '>': fetch(ixnew, c, d, f2, '>', 0, *pflags); break; default: printf("%%%c", *walk); break; } continue; } printf("%c", *walk); } } if (diff_format == D_SIDEBYSIDE) { if (color && a > b) printf("\033[%sm", add_code); else if (color && c > d) printf("\033[%sm", del_code); if (a > b) { print_space(0, hw + padding , *pflags); } else { nc = fetch(ixold, a, b, f1, '\0', 1, *pflags); print_space(nc, hw - nc + padding, *pflags); } if (color && a > b) printf("\033[%sm", add_code); else if (color && c > d) printf("\033[%sm", del_code); printf("%c", (a > b) ? '>' : ((c > d) ? '<' : '|')); if (color && c > d) printf("\033[m"); print_space(hw + padding + 1 , padding, *pflags); fetch(ixnew, c, d, f2, '\0', 0, *pflags); printf("\n"); } if (diff_format == D_NORMAL || diff_format == D_IFDEF) { fetch(ixold, a, b, f1, '<', 1, *pflags); if (a <= b && c <= d && diff_format == D_NORMAL) printf("---\n"); } if (diff_format != D_GFORMAT && diff_format != D_SIDEBYSIDE) fetch(ixnew, c, d, f2, diff_format == D_NORMAL ? '>' : '\0', 0, *pflags); if (edoffset != 0 && diff_format == D_EDIT) { /* * A non-zero edoffset value for D_EDIT indicates that the last line * printed was a bare dot (".") that has been escaped as ".." to * prevent ed(1) from misinterpreting it. We have to add a * substitute command to change this back and restart where we left * off. */ printf(".\n"); printf("%ds/.//\n", a + edoffset - 1); b = a + edoffset - 1; a = b + 1; c += edoffset; goto restart; } if ((diff_format == D_EDIT || diff_format == D_REVERSE) && c <= d) printf(".\n"); if (inifdef) { printf("#endif /* %s */\n", ifdefname); inifdef = 0; } } static int fetch(long *f, int a, int b, FILE *lb, int ch, int oldfile, int flags) { int i, j, c, lastc, col, nc, newcol; edoffset = 0; nc = 0; /* * When doing #ifdef's, copy down to current line * if this is the first file, so that stuff makes it to output. */ if ((diff_format == D_IFDEF) && oldfile) { long curpos = ftell(lb); /* print through if append (a>b), else to (nb: 0 vs 1 orig) */ nc = f[a > b ? b : a - 1] - curpos; for (i = 0; i < nc; i++) printf("%c", getc(lb)); } if (a > b) return (0); if (diff_format == D_IFDEF) { if (inifdef) { printf("#else /* %s%s */\n", oldfile == 1 ? "!" : "", ifdefname); } else { if (oldfile) printf("#ifndef %s\n", ifdefname); else printf("#ifdef %s\n", ifdefname); } inifdef = 1 + oldfile; } for (i = a; i <= b; i++) { fseek(lb, f[i - 1], SEEK_SET); nc = f[i] - f[i - 1]; if (diff_format == D_SIDEBYSIDE && hw < nc) nc = hw; if (diff_format != D_IFDEF && diff_format != D_GFORMAT && ch != '\0') { if (color && (ch == '>' || ch == '+')) printf("\033[%sm", add_code); else if (color && (ch == '<' || ch == '-')) printf("\033[%sm", del_code); printf("%c", ch); if (Tflag && (diff_format == D_NORMAL || diff_format == D_CONTEXT || diff_format == D_UNIFIED)) printf("\t"); else if (diff_format != D_UNIFIED) printf(" "); } col = j = 0; lastc = '\0'; while (j < nc && (hw == 0 || col < hw)) { c = getc(lb); if (flags & D_STRIPCR && c == '\r') { if ((c = getc(lb)) == '\n') j++; else { ungetc(c, lb); c = '\r'; } } if (c == EOF) { if (diff_format == D_EDIT || diff_format == D_REVERSE || diff_format == D_NREVERSE) warnx("No newline at end of file"); else printf("\n\\ No newline at end of file\n"); return (col); } /* * when using --side-by-side, col needs to be increased * in any case to keep the columns aligned */ if (c == '\t') { if (flags & D_EXPANDTABS) { newcol = ((col / tabsize) + 1) * tabsize; do { printf(" "); } while (++col < newcol && col < hw); } else { if (diff_format == D_SIDEBYSIDE) { if ((col + tabsize) > hw) { printf("%*s", hw - col, ""); col = hw; } else { printf("\t"); col += tabsize - 1; } } else { printf("\t"); col++; } } } else { if (diff_format == D_EDIT && j == 1 && c == '\n' && lastc == '.') { /* * Don't print a bare "." line since that will confuse * ed(1). Print ".." instead and set the, global variable * edoffset to an offset from which to restart. The * caller must check the value of edoffset */ printf(".\n"); edoffset = i - a + 1; return (edoffset); } /* when side-by-side, do not print a newline */ if (diff_format != D_SIDEBYSIDE || c != '\n') { if (color && c == '\n') printf("\033[m%c", c); else printf("%c", c); col++; } } j++; lastc = c; } } if (color && diff_format == D_SIDEBYSIDE) printf("\033[m"); return (col); } /* * Hash function taken from Robert Sedgewick, Algorithms in C, 3d ed., p 578. */ static enum readhash readhash(FILE *f, int flags, unsigned *hash) { int i, t, space; unsigned sum; sum = 1; space = 0; for (i = 0;;) { switch (t = getc(f)) { case '\0': if ((flags & D_FORCEASCII) == 0) return (RH_BINARY); goto hashchar; case '\r': if (flags & D_STRIPCR) { t = getc(f); if (t == '\n') break; ungetc(t, f); } /* FALLTHROUGH */ case '\t': case '\v': case '\f': case ' ': if ((flags & (D_FOLDBLANKS|D_IGNOREBLANKS)) != 0) { space++; continue; } /* FALLTHROUGH */ default: hashchar: if (space && (flags & D_IGNOREBLANKS) == 0) { i++; space = 0; } sum = sum * 127 + chrtran(t); i++; continue; case EOF: if (i == 0) return (RH_EOF); /* FALLTHROUGH */ case '\n': break; } break; } *hash = sum; return (RH_OK); } static int asciifile(FILE *f) { unsigned char buf[BUFSIZ]; size_t cnt; if (f == NULL) return (1); rewind(f); cnt = fread(buf, 1, sizeof(buf), f); return (memchr(buf, '\0', cnt) == NULL); } #define begins_with(s, pre) (strncmp(s, pre, sizeof(pre) - 1) == 0) static char * match_function(const long *f, int pos, FILE *fp) { unsigned char buf[FUNCTION_CONTEXT_SIZE]; size_t nc; int last = lastline; const char *state = NULL; lastline = pos; for (; pos > last; pos--) { fseek(fp, f[pos - 1], SEEK_SET); nc = f[pos] - f[pos - 1]; if (nc >= sizeof(buf)) nc = sizeof(buf) - 1; nc = fread(buf, 1, nc, fp); if (nc == 0) continue; buf[nc] = '\0'; buf[strcspn(buf, "\n")] = '\0'; if (most_recent_pat != NULL) { int ret = regexec(&most_recent_re, buf, 0, NULL, 0); if (ret != 0) continue; strlcpy(lastbuf, buf, sizeof(lastbuf)); lastmatchline = pos; return (lastbuf); } else if (isalpha(buf[0]) || buf[0] == '_' || buf[0] == '$' || buf[0] == '-' || buf[0] == '+') { if (begins_with(buf, "private:")) { if (!state) state = " (private)"; } else if (begins_with(buf, "protected:")) { if (!state) state = " (protected)"; } else if (begins_with(buf, "public:")) { if (!state) state = " (public)"; } else { strlcpy(lastbuf, buf, sizeof(lastbuf)); if (state) strlcat(lastbuf, state, sizeof(lastbuf)); lastmatchline = pos; return (lastbuf); } } } return (lastmatchline > 0 ? lastbuf : NULL); } /* dump accumulated "context" diff changes */ static void dump_context_vec(FILE *f1, FILE *f2, int flags) { struct context_vec *cvp = context_vec_start; int lowa, upb, lowc, upd, do_output; int a, b, c, d; char ch, *f; if (context_vec_start > context_vec_ptr) return; b = d = 0; /* gcc */ lowa = MAX(1, cvp->a - diff_context); upb = MIN(len[0], context_vec_ptr->b + diff_context); lowc = MAX(1, cvp->c - diff_context); upd = MIN(len[1], context_vec_ptr->d + diff_context); printf("***************"); if (flags & (D_PROTOTYPE | D_MATCHLAST)) { f = match_function(ixold, cvp->a - 1, f1); if (f != NULL) printf(" %s", f); } printf("\n*** "); range(lowa, upb, ","); printf(" ****\n"); /* * Output changes to the "old" file. The first loop suppresses * output if there were no changes to the "old" file (we'll see * the "old" lines as context in the "new" list). */ do_output = 0; for (; cvp <= context_vec_ptr; cvp++) if (cvp->a <= cvp->b) { cvp = context_vec_start; do_output++; break; } if (do_output) { while (cvp <= context_vec_ptr) { a = cvp->a; b = cvp->b; c = cvp->c; d = cvp->d; if (a <= b && c <= d) ch = 'c'; else ch = (a <= b) ? 'd' : 'a'; if (ch == 'a') fetch(ixold, lowa, b, f1, ' ', 0, flags); else { fetch(ixold, lowa, a - 1, f1, ' ', 0, flags); fetch(ixold, a, b, f1, ch == 'c' ? '!' : '-', 0, flags); } lowa = b + 1; cvp++; } fetch(ixold, b + 1, upb, f1, ' ', 0, flags); } /* output changes to the "new" file */ printf("--- "); range(lowc, upd, ","); printf(" ----\n"); do_output = 0; for (cvp = context_vec_start; cvp <= context_vec_ptr; cvp++) if (cvp->c <= cvp->d) { cvp = context_vec_start; do_output++; break; } if (do_output) { while (cvp <= context_vec_ptr) { a = cvp->a; b = cvp->b; c = cvp->c; d = cvp->d; if (a <= b && c <= d) ch = 'c'; else ch = (a <= b) ? 'd' : 'a'; if (ch == 'd') fetch(ixnew, lowc, d, f2, ' ', 0, flags); else { fetch(ixnew, lowc, c - 1, f2, ' ', 0, flags); fetch(ixnew, c, d, f2, ch == 'c' ? '!' : '+', 0, flags); } lowc = d + 1; cvp++; } fetch(ixnew, d + 1, upd, f2, ' ', 0, flags); } context_vec_ptr = context_vec_start - 1; } /* dump accumulated "unified" diff changes */ static void dump_unified_vec(FILE *f1, FILE *f2, int flags) { struct context_vec *cvp = context_vec_start; int lowa, upb, lowc, upd; int a, b, c, d; char ch, *f; if (context_vec_start > context_vec_ptr) return; b = d = 0; /* gcc */ lowa = MAX(1, cvp->a - diff_context); upb = MIN(len[0], context_vec_ptr->b + diff_context); lowc = MAX(1, cvp->c - diff_context); upd = MIN(len[1], context_vec_ptr->d + diff_context); printf("@@ -"); uni_range(lowa, upb); printf(" +"); uni_range(lowc, upd); printf(" @@"); if (flags & (D_PROTOTYPE | D_MATCHLAST)) { f = match_function(ixold, cvp->a - 1, f1); if (f != NULL) printf(" %s", f); } printf("\n"); /* * Output changes in "unified" diff format--the old and new lines * are printed together. */ for (; cvp <= context_vec_ptr; cvp++) { a = cvp->a; b = cvp->b; c = cvp->c; d = cvp->d; /* * c: both new and old changes * d: only changes in the old file * a: only changes in the new file */ if (a <= b && c <= d) ch = 'c'; else ch = (a <= b) ? 'd' : 'a'; switch (ch) { case 'c': fetch(ixold, lowa, a - 1, f1, ' ', 0, flags); fetch(ixold, a, b, f1, '-', 0, flags); fetch(ixnew, c, d, f2, '+', 0, flags); break; case 'd': fetch(ixold, lowa, a - 1, f1, ' ', 0, flags); fetch(ixold, a, b, f1, '-', 0, flags); break; case 'a': fetch(ixnew, lowc, c - 1, f2, ' ', 0, flags); fetch(ixnew, c, d, f2, '+', 0, flags); break; } lowa = b + 1; lowc = d + 1; } fetch(ixnew, d + 1, upd, f2, ' ', 0, flags); context_vec_ptr = context_vec_start - 1; } static void print_header(const char *file1, const char *file2) { const char *time_format; char buf[256]; struct tm tm1, tm2, *tm_ptr1, *tm_ptr2; int nsec1 = stb1.st_mtim.tv_nsec; int nsec2 = stb2.st_mtim.tv_nsec; time_format = "%Y-%m-%d %H:%M:%S"; if (cflag) time_format = "%c"; tm_ptr1 = localtime_r(&stb1.st_mtime, &tm1); tm_ptr2 = localtime_r(&stb2.st_mtime, &tm2); if (label[0] != NULL) printf("%s %s\n", diff_format == D_CONTEXT ? "***" : "---", label[0]); else { strftime(buf, sizeof(buf), time_format, tm_ptr1); printf("%s %s\t%s", diff_format == D_CONTEXT ? "***" : "---", file1, buf); if (!cflag) { strftime(buf, sizeof(buf), "%z", tm_ptr1); printf(".%.9d %s", nsec1, buf); } printf("\n"); } if (label[1] != NULL) printf("%s %s\n", diff_format == D_CONTEXT ? "---" : "+++", label[1]); else { strftime(buf, sizeof(buf), time_format, tm_ptr2); printf("%s %s\t%s", diff_format == D_CONTEXT ? "---" : "+++", file2, buf); if (!cflag) { strftime(buf, sizeof(buf), "%z", tm_ptr2); printf(".%.9d %s", nsec2, buf); } printf("\n"); } } /* * Prints n number of space characters either by using tab * or single space characters. * nc is the preceding number of characters */ static void print_space(int nc, int n, int flags) { int i, col; col = n; if ((flags & D_EXPANDTABS) == 0) { /* first tabstop may be closer than tabsize */ i = tabsize - (nc % tabsize); while (col >= tabsize) { printf("\t"); col -= i; i = tabsize; } } printf("%*s", col, ""); }