get_data_path.c

seed格式数据解压程序,地震分析人员必备

/*===========================================================================*/
/* DMC interim out |            get_data_path              |         utility */
/*===========================================================================*/
/*
	Name:		get_data_path
	Purpose:	recover base location for SEED data from environment
	Usage:		struct path_list *get_data_path ();
	Input:		Environment Variable "DATA_PATH"
				of the form, "a:b:c:d"
	Output:		a pointer to a circularly linked list of struct path_list
	Externals:	none
	Messages:	none
	Warnings:	none
	Errors:		none
	Fatals:		none
	Called by:	anything
	Calls to:	none
	Algorithm:	read the value of the environment variable DATA_PATH
				and parse it, constructing the list. If there is no
				DATA_PATH, default to value of string "noenv".
	Notes:		usually called from main routine
	Problems:	none known
	Debug:		not used
	References:	none
	Language:	C
	Revisions:	04mar89 mark wiederspahn	created, overwritten, retyped
	19nov90		mw		change error level if no DATA_PATH in environment
						from WARNING to FATAL - ain't no point to continue.
*/

#include <stdlib.h>
#include "globals.h"
#include "output.h"


struct path_list *get_data_path ()
{
char *p, *lp;							/* ptr to value of DATA_PATH */
struct	path_list	*head, *tail;

static char noenv[] = "cache";			/* default directory */

/* Used for my testing - make sure to have ending '/' */
static char *tmp_path = "/seed/0010142002/data_files/";


	if( (p = (char *)getenv("DATA_PATH")) != NULL )
	{
		head = NULL;
		tail = NULL;
		lp = p;
		while( lp >= p )					/* while other places to scan */
		{
			while( *p !=  0 && *p != ':' ) p++;	/* find terminator */
			if( head == NULL )
				head = tail =
					(struct path_list *)
						malloc( sizeof(struct path_list) );
			else
			{
				tail->next =
					(struct path_list *)
						malloc( sizeof(struct path_list) );
				tail = tail->next;
			}
			tail->next = NULL;


#if 0

/* #### added tmp_path for debugging and testing CL #### */
			tail->path = (char *)malloc( sizeof(char)*(p-lp+1) + strlen(tmp_path));

			strcpy(tail->path, tmp_path);

/* ### changed strncpy to strcat - took out terminator line### */

			strncat( tail->path, lp, (p-lp) );

		/* 	*(tail->path+(p-lp+1)) = 0; */
#else
			tail->path = (char *)malloc(sizeof(char)*(p-lp+1));

			strncpy(tail->path, lp, (p-lp));
 
            *(tail->path+(p-lp)) = 0;

#endif


			if( *p != 0) p = lp = p+1;		/* if not end, set for next */
		}
	}
	else
	{
			head = tail =
				(struct path_list *)
					malloc( sizeof(struct path_list) );
			tail->path = noenv;

			if (!Write_Data)
				error_handler( FATAL,
					"[get_data_path] environment DATA_PATH not defined" );
	}
	tail->next = head;
	return( head );
}