pch.c

来自「这是一个同样来自贝尔实验室的和UNIX有着渊源的操作系统, 其简洁的设计和实现易」· C语言 代码 · 共 1,866 行 · 第 1/4 页

		  s++;
		if (*s == ',')
		  {
		    do
		      {
			if (!*++s)
			  malformed ();
		      }
		    while (! ISDIGIT (*s));
		    p_repl_lines = (LINENUM) atol (s) - p_newfirst + 1;
		  }
		else if (p_newfirst)
		  p_repl_lines = 1;
		else
		  {
		    p_repl_lines = 0;
		    p_newfirst = 1;
		  }
		p_max = p_repl_lines + p_end;
		while (p_max >= hunkmax)
		  if (! grow_hunkmax ())
		    return -1;
		if (p_repl_lines != ptrn_copiable
		    && (p_prefix_context != 0
			|| context != 0
			|| p_repl_lines != 1))
		  repl_could_be_missing = FALSE;
		context = 0;
		break;
	    case '+':  case '!':
		repl_could_be_missing = FALSE;
	      change_line:
		s = buf + 1;
		chars_read--;
		if (*s == '\n' && canonicalize) {
		    strcpy (s, " \n");
		    chars_read = 2;
		}
		if (*s == ' ' || *s == '\t') {
		    s++;
		    chars_read--;
		} else if (repl_beginning && repl_could_be_missing) {
		    repl_missing = TRUE;
		    goto hunk_done;
		}
		if (! repl_beginning)
		  {
		    if (ptrn_prefix_context == -1)
		      ptrn_prefix_context = context;
		  }
		else
		  {
		    if (repl_prefix_context == -1)
		      repl_prefix_context = context;
		  }
		chars_read -=
		  (1 < chars_read
		   && p_end == (repl_beginning ? p_max : p_ptrn_lines)
		   && incomplete_line ());
		p_len[p_end] = chars_read;
		if (! (p_line[p_end] = savebuf (s, chars_read))) {
		    p_end--;
		    return -1;
		}
		context = 0;
		break;
	    case '\t': case '\n':	/* assume spaces got eaten */
		s = buf;
		if (*buf == '\t') {
		    s++;
		    chars_read--;
		}
		if (repl_beginning && repl_could_be_missing &&
		    (!ptrn_spaces_eaten || difftype == NEW_CONTEXT_DIFF) ) {
		    repl_missing = TRUE;
		    goto hunk_done;
		}
		chars_read -=
		  (1 < chars_read
		   && p_end == (repl_beginning ? p_max : p_ptrn_lines)
		   && incomplete_line ());
		p_len[p_end] = chars_read;
		if (! (p_line[p_end] = savebuf (buf, chars_read))) {
		    p_end--;
		    return -1;
		}
		if (p_end != p_ptrn_lines + 1) {
		    ptrn_spaces_eaten |= (repl_beginning != 0);
		    some_context = TRUE;
		    context++;
		    if (!repl_beginning)
			ptrn_copiable++;
		    p_Char[p_end] = ' ';
		}
		break;
	    case ' ':
		s = buf + 1;
		chars_read--;
		if (*s == '\n' && canonicalize) {
		    strcpy (s, "\n");
		    chars_read = 2;
		}
		if (*s == ' ' || *s == '\t') {
		    s++;
		    chars_read--;
		} else if (repl_beginning && repl_could_be_missing) {
		    repl_missing = TRUE;
		    goto hunk_done;
		}
		some_context = TRUE;
		context++;
		if (!repl_beginning)
		    ptrn_copiable++;
		chars_read -=
		  (1 < chars_read
		   && p_end == (repl_beginning ? p_max : p_ptrn_lines)
		   && incomplete_line ());
		p_len[p_end] = chars_read;
		if (! (p_line[p_end] = savebuf (buf + 2, chars_read))) {
		    p_end--;
		    return -1;
		}
		break;
	    default:
		if (repl_beginning && repl_could_be_missing) {
		    repl_missing = TRUE;
		    goto hunk_done;
		}
		malformed ();
	    }
	}

    hunk_done:
	if (p_end >=0 && !repl_beginning)
	    fatal ("no `---' found in patch at line %ld", pch_hunk_beg ());

	if (repl_missing) {

	    /* reset state back to just after --- */
	    p_input_line = repl_patch_line;
	    context = repl_context;
	    for (p_end--; p_end > repl_beginning; p_end--)
		free(p_line[p_end]);
	    Fseek (pfp, repl_backtrack_position, SEEK_SET);

	    /* redundant 'new' context lines were omitted - set */
	    /* up to fill them in from the old file context */
	    fillsrc = 1;
	    filldst = repl_beginning+1;
	    fillcnt = p_repl_lines;
	    p_end = p_max;
	}
	else if (!some_context && fillcnt == 1) {
	    /* the first hunk was a null hunk with no context */
	    /* and we were expecting one line -- fix it up. */
	    while (filldst < p_end) {
		p_line[filldst] = p_line[filldst+1];
		p_Char[filldst] = p_Char[filldst+1];
		p_len[filldst] = p_len[filldst+1];
		filldst++;
	    }
#if 0
	    repl_beginning--;		/* this doesn't need to be fixed */
#endif
	    p_end--;
	    p_first++;			/* do append rather than insert */
	    fillcnt = 0;
	    p_ptrn_lines = 0;
	}

	p_prefix_context = ((repl_prefix_context == -1
			     || (ptrn_prefix_context != -1
				 && ptrn_prefix_context < repl_prefix_context))
			    ? ptrn_prefix_context : repl_prefix_context);
	p_suffix_context = ((ptrn_suffix_context != -1
			     && ptrn_suffix_context < context)
			    ? ptrn_suffix_context : context);
	assert (p_prefix_context != -1 && p_suffix_context != -1);

	if (difftype == CONTEXT_DIFF
	    && (fillcnt
		|| (p_first > 1
		    && p_prefix_context + p_suffix_context < ptrn_copiable))) {
	    if (verbosity == VERBOSE)
		say ("%s\n%s\n%s\n",
"(Fascinating -- this is really a new-style context diff but without",
"the telltale extra asterisks on the *** line that usually indicate",
"the new style...)");
	    diff_type = difftype = NEW_CONTEXT_DIFF;
	}

	/* if there were omitted context lines, fill them in now */
	if (fillcnt) {
	    p_bfake = filldst;		/* remember where not to free() */
	    p_efake = filldst + fillcnt - 1;
	    while (fillcnt-- > 0) {
		while (fillsrc <= p_end && fillsrc != repl_beginning
		       && p_Char[fillsrc] != ' ')
		    fillsrc++;
		if (p_end < fillsrc || fillsrc == repl_beginning)
		    fatal ("replacement text or line numbers mangled in hunk at line %ld",
			p_hunk_beg);
		p_line[filldst] = p_line[fillsrc];
		p_Char[filldst] = p_Char[fillsrc];
		p_len[filldst] = p_len[fillsrc];
		fillsrc++; filldst++;
	    }
	    while (fillsrc <= p_end && fillsrc != repl_beginning)
	      {
		if (p_Char[fillsrc] == ' ')
		  fatal ("replacement text or line numbers mangled in hunk at line %ld",
			 p_hunk_beg);
		fillsrc++;
	      }
	    if (debug & 64)
		printf("fillsrc %ld, filldst %ld, rb %ld, e+1 %ld\n",
		    fillsrc,filldst,repl_beginning,p_end+1);
	    assert(fillsrc==p_end+1 || fillsrc==repl_beginning);
	    assert(filldst==p_end+1 || filldst==repl_beginning);
	}
    }
    else if (difftype == UNI_DIFF) {
	file_offset line_beginning = file_tell (pfp);
					/* file pos of the current line */
	register LINENUM fillsrc;	/* index of old lines */
	register LINENUM filldst;	/* index of new lines */
	char ch = '\0';

	chars_read = get_line ();
	if (chars_read == (size_t) -1
	    || chars_read <= 4
	    || strncmp (buf, "@@ -", 4) != 0) {
	    next_intuit_at(line_beginning,p_input_line);
	    return chars_read == (size_t) -1 ? -1 : 0;
	}
	s = buf+4;
	if (!*s)
	    malformed ();
	p_first = (LINENUM) atol(s);
	while (ISDIGIT (*s))
	  s++;
	if (*s == ',') {
	    p_ptrn_lines = (LINENUM) atol(++s);
	    while (ISDIGIT (*s))
	      s++;
	} else
	    p_ptrn_lines = 1;
	if (*s == ' ') s++;
	if (*s != '+' || !*++s)
	    malformed ();
	p_newfirst = (LINENUM) atol(s);
	while (ISDIGIT (*s))
	  s++;
	if (*s == ',') {
	    p_repl_lines = (LINENUM) atol(++s);
	    while (ISDIGIT (*s))
	      s++;
	} else
	    p_repl_lines = 1;
	if (*s == ' ') s++;
	if (*s != '@')
	    malformed ();
	if (!p_ptrn_lines)
	    p_first++;			/* do append rather than insert */
	if (!p_repl_lines)
	    p_newfirst++;
	p_max = p_ptrn_lines + p_repl_lines + 1;
	while (p_max >= hunkmax)
	    if (! grow_hunkmax ())
		return -1;
	fillsrc = 1;
	filldst = fillsrc + p_ptrn_lines;
	p_end = filldst + p_repl_lines;
	sprintf (buf,"*** %ld,%ld ****\n",p_first,p_first + p_ptrn_lines - 1);
	p_len[0] = strlen (buf);
	if (! (p_line[0] = savestr (buf))) {
	    p_end = -1;
	    return -1;
	}
	p_Char[0] = '*';
	sprintf (buf,"--- %ld,%ld ----\n",p_newfirst,p_newfirst+p_repl_lines-1);
	p_len[filldst] = strlen (buf);
	if (! (p_line[filldst] = savestr (buf))) {
	    p_end = 0;
	    return -1;
	}
	p_Char[filldst++] = '=';
	p_prefix_context = -1;
	p_hunk_beg = p_input_line + 1;
	while (fillsrc <= p_ptrn_lines || filldst <= p_end) {
	    chars_read = get_line ();
	    if (!chars_read) {
		if (p_max - filldst < 3) {
		    strcpy (buf, " \n");  /* assume blank lines got chopped */
		    chars_read = 2;
		} else {
		    fatal ("unexpected end of file in patch");
		}
	    }
	    if (chars_read == (size_t) -1)
		s = 0;
	    else if (*buf == '\t' || *buf == '\n') {
		ch = ' ';		/* assume the space got eaten */
		s = savebuf (buf, chars_read);
	    }
	    else {
		ch = *buf;
		s = savebuf (buf+1, --chars_read);
	    }
	    if (!s) {
		while (--filldst > p_ptrn_lines)
		    free(p_line[filldst]);
		p_end = fillsrc-1;
		return -1;
	    }
	    switch (ch) {
	    case '-':
		if (fillsrc > p_ptrn_lines) {
		    free(s);
		    p_end = filldst-1;
		    malformed ();
		}
		chars_read -= fillsrc == p_ptrn_lines && incomplete_line ();
		p_Char[fillsrc] = ch;
		p_line[fillsrc] = s;
		p_len[fillsrc++] = chars_read;
		break;
	    case '=':
		ch = ' ';
		/* FALL THROUGH */
	    case ' ':
		if (fillsrc > p_ptrn_lines) {
		    free(s);
		    while (--filldst > p_ptrn_lines)
			free(p_line[filldst]);
		    p_end = fillsrc-1;
		    malformed ();
		}
		context++;
		chars_read -= fillsrc == p_ptrn_lines && incomplete_line ();
		p_Char[fillsrc] = ch;
		p_line[fillsrc] = s;
		p_len[fillsrc++] = chars_read;
		s = savebuf (s, chars_read);
		if (!s) {
		    while (--filldst > p_ptrn_lines)
			free(p_line[filldst]);
		    p_end = fillsrc-1;
		    return -1;
		}
		/* FALL THROUGH */
	    case '+':
		if (filldst > p_end) {
		    free(s);
		    while (--filldst > p_ptrn_lines)
			free(p_line[filldst]);
		    p_end = fillsrc-1;
		    malformed ();
		}
		chars_read -= filldst == p_end && incomplete_line ();
		p_Char[filldst] = ch;
		p_line[filldst] = s;
		p_len[filldst++] = chars_read;
		break;
	    default:
		p_end = filldst;
		malformed ();
	    }
	    if (ch != ' ') {
		if (p_prefix_context == -1)
		    p_prefix_context = context;
		context = 0;
	    }
	}/* while */
	if (p_prefix_context == -1)
	  malformed ();
	p_suffix_context = context;
    }
    else {				/* normal diff--fake it up */
	char hunk_type;
	register int i;
	LINENUM min, max;
	file_offset line_beginning = file_tell (pfp);

	p_prefix_context = p_suffix_context = 0;
	chars_read = get_line ();
	if (chars_read == (size_t) -1 || !chars_read || !ISDIGIT (*buf)) {
	    next_intuit_at(line_beginning,p_input_line);
	    return chars_read == (size_t) -1 ? -1 : 0;
	}
	p_first = (LINENUM)atol(buf);
	for (s = buf;  ISDIGIT (*s);  s++)
	  continue;
	if (*s == ',') {
	    p_ptrn_lines = (LINENUM)atol(++s) - p_first + 1;
	    while (ISDIGIT (*s))
	      s++;
	}
	else
	    p_ptrn_lines = (*s != 'a');
	hunk_type = *s;
	if (hunk_type == 'a')
	    p_first++;			/* do append rather than insert */
	min = (LINENUM)atol(++s);
	while (ISDIGIT (*s))
	  s++;
	if (*s == ',')
	    max = (LINENUM)atol(++s);
	else
	    max = min;
	if (hunk_type == 'd')
	    min++;
	p_end = p_ptrn_lines + 1 + max - min + 1;
	while (p_end >= hunkmax)
	  if (! grow_hunkmax ())
	    {
	      p_end = -1;
	      return -1;
	    }
	p_newfirst = min;
	p_repl_lines = max - min + 1;
	sprintf (buf, "*** %ld,%ld\n", p_first, p_first + p_ptrn_lines - 1);
	p_len[0] = strlen (buf);
	if (! (p_line[0] = savestr (buf))) {
	    p_end = -1;
	    return -1;
	}
	p_Char[0] = '*';
	for (i=1; i<=p_ptrn_lines; i++) {
	    chars_read = get_line ();
	    if (chars_read == (size_t) -1)
	      {
		p_end = i - 1;
		return -1;
	      }
	    if (!chars_read)
		fatal ("unexpected end of file in patch at line %ld",
		  p_input_line);
	    if (buf[0] != '<' || (buf[1] != ' ' && buf[1] != '\t'))
		fatal ("`<' expected at line %ld of patch", p_input_line);
	    chars_read -= 2 + (i == p_ptrn_lines && incomplete_line ());
	    p_len[i] = chars_read;
	    if (! (p_line[i] = savebuf (buf + 2, chars_read))) {
		p_end = i-1;
		return -1;
	    }
	    p_Char[i] = '-';
	}
	if (hunk_type == 'c') {
	    chars_read = get_line ();
	    if (chars_read == (size_t) -1)
	      {
		p_end = i - 1;
		return -1;
	      }
	    if (! chars_read)
		fatal ("unexpected end of file in patch at line %ld",
		    p_input_line);
	    if (*buf != '-')
		fatal ("`---' expected at line %ld of patch", p_input_line);
	}
	sprintf (buf, "--- %ld,%ld\n", min, max);
	p_len[i] = strlen (buf);
	if (! (p_line[i] = savestr (buf))) {
	    p_end = i-1;
	    return -1;
	}