/* * split-include.c * * Copyright abandoned, Michael Chastain, <mailto:mec@shout.net>. * This is a C version of syncdep.pl by Werner Almesberger. * * This program takes autoconf.h as input and outputs a directory full * of one-line include files, merging onto the old values. * * Think of the configuration options as key-value pairs.  Then there * are five cases: * *    key      old value   new value   action * *    KEY-1    VALUE-1     VALUE-1     leave file alone *    KEY-2    VALUE-2A    VALUE-2B    write VALUE-2B into file *    KEY-3    -           VALUE-3     write VALUE-3  into file *    KEY-4    VALUE-4     -           write an empty file *    KEY-5    (empty)     -           leave old empty file alone */#include <sys/types.h>#include <sys/stat.h>#include <ctype.h>#include <errno.h>#include <fcntl.h>#include <stdio.h>#include <stdlib.h>#include <string.h>#include <unistd.h>#define ERROR_EXIT(strExit)						\    {									\	const int errnoSave = errno;					\	fprintf(stderr, "%s: ", str_my_name);				\	errno = errnoSave;						\	perror((strExit));						\	exit(1);							\    }int main(int argc, const char * argv []){    const char * str_my_name;    const char * str_file_autoconf;    const char * str_dir_config;    FILE * fp_config;    FILE * fp_target;    FILE * fp_find;    int buffer_size;    char * line;    char * old_line;    char * list_target;    char * ptarget;    struct stat stat_buf;    /* Check arg count. */    if (argc != 3)    {	fprintf(stderr, "%s: wrong number of arguments.\n", argv[0]);	exit(1);    }    str_my_name       = argv[0];    str_file_autoconf = argv[1];    str_dir_config    = argv[2];    /* Find a buffer size. */    if (stat(str_file_autoconf, &stat_buf) != 0)	ERROR_EXIT(str_file_autoconf);    buffer_size = 2 * stat_buf.st_size + 4096;    /* Allocate buffers. */    if ( (line        = malloc(buffer_size)) == NULL    ||   (old_line    = malloc(buffer_size)) == NULL    ||   (list_target = malloc(buffer_size)) == NULL )	ERROR_EXIT(str_file_autoconf);    /* Open autoconfig file. */    if ((fp_config = fopen(str_file_autoconf, "r")) == NULL)	ERROR_EXIT(str_file_autoconf);    /* Make output directory if needed. */    if (stat(str_dir_config, &stat_buf) != 0)    {	if (mkdir(str_dir_config, 0755) != 0)	    ERROR_EXIT(str_dir_config);    }    /* Change to output directory. */    if (chdir(str_dir_config) != 0)	ERROR_EXIT(str_dir_config);	    /* Put initial separator into target list. */    ptarget = list_target;    *ptarget++ = '\n';    /* Read config lines. */    while (fgets(line, buffer_size, fp_config))    {	const char * str_config;	int is_same;	int itarget;	if (line[0] != '#')	    continue;	if ((str_config = strstr(line, "CONFIG_")) == NULL)	    continue;	/* Make the output file name. */	str_config += sizeof("CONFIG_") - 1;	for (itarget = 0; !isspace((int)str_config[itarget]); itarget++)	{	    char c = str_config[itarget];	    if (isupper((int)c)) c = tolower((int)c);	    if (c == '_')   c = '/';	    ptarget[itarget] = c;	}	ptarget[itarget++] = '.';	ptarget[itarget++] = 'h';	ptarget[itarget++] = '\0';	/* Check for existing file. */	is_same = 0;	if ((fp_target = fopen(ptarget, "r")) != NULL)	{	    fgets(old_line, buffer_size, fp_target);	    if (fclose(fp_target) != 0)		ERROR_EXIT(ptarget);	    if (!strcmp(line, old_line))		is_same = 1;	}	if (!is_same)	{	    /* Auto-create directories. */	    int islash;	    for (islash = 0; islash < itarget; islash++)	    {		if (ptarget[islash] == '/')		{		    ptarget[islash] = '\0';		    if (stat(ptarget, &stat_buf) != 0		    &&  mkdir(ptarget, 0755)     != 0)			ERROR_EXIT( ptarget );		    ptarget[islash] = '/';		}	    }	    /* Write the file. */	    if ((fp_target = fopen(ptarget, "w" )) == NULL)		ERROR_EXIT(ptarget);	    fputs(line, fp_target);	    if (ferror(fp_target) || fclose(fp_target) != 0)		ERROR_EXIT(ptarget);	}	/* Update target list */	ptarget += itarget;	*(ptarget-1) = '\n';    }    /*     * Close autoconfig file.     * Terminate the target list.     */    if (fclose(fp_config) != 0)	ERROR_EXIT(str_file_autoconf);    *ptarget = '\0';    /*     * Fix up existing files which have no new value.     * This is Case 4 and Case 5.     *     * I re-read the tree and filter it against list_target.     * This is crude.  But it avoids data copies.  Also, list_target     * is compact and contiguous, so it easily fits into cache.     *     * Notice that list_target contains strings separated by \n,     * with a \n before the first string and after the last.     * fgets gives the incoming names a terminating \n.     * So by having an initial \n, strstr will find exact matches.     */    fp_find = popen("find * -type f -name \"*.h\" -print", "r");    if (fp_find == 0)	ERROR_EXIT( "find" );    line[0] = '\n';    while (fgets(line+1, buffer_size, fp_find))    {	if (strstr(list_target, line) == NULL)	{	    /*	     * This is an old file with no CONFIG_* flag in autoconf.h.	     */	    /* First strip the \n. */	    line[strlen(line)-1] = '\0';	    /* Grab size. */	    if (stat(line+1, &stat_buf) != 0)		ERROR_EXIT(line);	    /* If file is not empty, make it empty and give it a fresh date. */	    if (stat_buf.st_size != 0)	    {		if ((fp_target = fopen(line+1, "w")) == NULL)		    ERROR_EXIT(line);		if (fclose(fp_target) != 0)		    ERROR_EXIT(line);	    }	}    }    if (pclose(fp_find) != 0)	ERROR_EXIT("find");    return 0;}