diff options
Diffstat (limited to 'expand.c')
| -rw-r--r-- | expand.c | 80 |
1 files changed, 66 insertions, 14 deletions
@@ -1,5 +1,5 @@ /* Variable expansion functions for GNU Make. -Copyright (C) 1988, 1989, 1991 Free Software Foundation, Inc. +Copyright (C) 1988, 1989, 1991, 1992 Free Software Foundation, Inc. This file is part of GNU Make. GNU Make is free software; you can redistribute it and/or modify @@ -21,7 +21,59 @@ the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */ #include "file.h" #include "variable.h" +/* The next two describe the variable output buffer. + This buffer is used to hold the variable-expansion of a line of the + makefile. It is made bigger with realloc whenever it is too small. + variable_buffer_length is the size currently allocated. + variable_buffer is the address of the buffer. */ +static unsigned int variable_buffer_length; +static char *variable_buffer; + +/* Subroutine of variable_expand and friends: + The text to add is LENGTH chars starting at STRING to the variable_buffer. + The text is added to the buffer at PTR, and the updated pointer into + the buffer is returned as the value. Thus, the value returned by + each call to variable_buffer_output should be the first argument to + the following call. */ + +static char * +variable_buffer_output (ptr, string, length) + char *ptr, *string; + unsigned int length; +{ + register unsigned int newlen = length + (ptr - variable_buffer); + + if (newlen > variable_buffer_length) + { + unsigned int offset = ptr - variable_buffer; + variable_buffer_length = max (2 * variable_buffer_length, newlen + 100); + variable_buffer = (char *) xrealloc (variable_buffer, + variable_buffer_length); + ptr = variable_buffer + offset; + } + + bcopy (string, ptr, length); + return ptr + length; +} + +/* Return a pointer to the beginning of the variable buffer. */ + +static char * +initialize_variable_output () +{ + /* If we don't have a variable output buffer yet, get one. */ + + if (variable_buffer == 0) + { + variable_buffer_length = 200; + variable_buffer = (char *) xmalloc (variable_buffer_length); + variable_buffer[0] = '\0'; + } + + return variable_buffer; +} + /* Recursively expand V. The returned string is malloc'd. */ static char * @@ -313,30 +365,30 @@ variable_expand_for_file (line, file) return result; } -/* Like variable_expand, but the returned string is malloc'd. */ -char * -allocated_variable_expand (line) - char *line; -{ - return allocated_variable_expand_for_file (line, (struct file *) 0); -} - -/* Like variable_expand_for_file, but the returned string is malloc'd. */ +/* Like variable_expand_for_file, but the returned string is malloc'd. + This function is called a lot. It wants to be efficient. */ char * allocated_variable_expand_for_file (line, file) char *line; struct file *file; { - char *save; char *value; - save = save_variable_output (); + char *obuf = variable_buffer; + unsigned int olen = variable_buffer_length; + + variable_buffer = 0; value = variable_expand_for_file (line, file); - value = savestring (value, strlen (value)); - restore_variable_output (save); +#if 0 + /* Waste a little memory and save time. */ + value = xrealloc (value, strlen (value)) +#endif + + variable_buffer = obuf; + variable_buffer_length = olen; return value; } |