unpack.c File Reference

Provides functions for determining unpacking types and opening unpacked files. More...

#include "mdb.h"
#include "scan.h"

Go to the source code of this file.

Macros
#define	UNPACK_TYPES   3

Functions
long	PackSuffixType (char *filename, char **unpackedName, unsigned long mode)
	Determines the unpacking type based on the file extension.
FILE *	UnpackFopen (char *filename, unsigned long mode, short *popenUsed, char **tmpFileUsed)
	Opens a file, potentially unpacking it based on its extension and mode.

Variables
static char *	unpackSuffix [UNPACK_TYPES]
static char *	unpackCommand [UNPACK_TYPES]

Detailed Description

Provides functions for determining unpacking types and opening unpacked files.

Copyright

• (c) 2002 The University of Chicago, as Operator of Argonne National Laboratory.
• (c) 2002 The Regents of the University of California, as Operator of Los Alamos National Laboratory.

License

This file is distributed under the terms of the Software License Agreement found in the file LICENSE included with this distribution.

Author

M. Borland, C Saunders, R. Soliday

Definition in file unpack.c.

Macro Definition Documentation

UNPACK_TYPES

#define UNPACK_TYPES   3

Definition at line 23 of file unpack.c.

Function Documentation

PackSuffixType()

long PackSuffixType	(	char *	filename,
		char **	unpackedName,
		unsigned long	mode )

Determines the unpacking type based on the file extension.

This function checks the file extension of the given filename to determine the type of unpacking required. It can optionally provide the unpacked filename without its extension and verify if the file conforms to the SDDS format if the UNPACK_REQUIRE_SDDS flag is set in the mode.

Parameters

filename	The name of the file to check.
unpackedName	Pointer to store the unpacked filename without extension (optional).
mode	Flags indicating unpacking requirements and options.

Returns

The index of the unpacking type if the extension matches, or -1 if no matching type is found or an error occurs.

Definition at line 47 of file unpack.c.

                                                                             {
  char *extension, buffer[10];
  FILE *fp;
  long i;
 
  if (!(extension = strrchr(filename, '.')))
    return -1;
 
  extension++;
  for (i = 0; i < UNPACK_TYPES; i++)
    if (strcmp(extension, unpackSuffix[i]) == 0) {
      if (unpackedName) {
        cp_str(unpackedName, filename);
        extension = strrchr(*unpackedName, '.');
        *extension = 0;
      }
      break;
    }
  if (i == UNPACK_TYPES)
    return -1;
 
  if (mode & UNPACK_REQUIRE_SDDS) {
    if (!(fp = fopen(filename, FOPEN_READ_MODE)))
      return -1;
    if (fread(buffer, sizeof(*buffer), 4, fp) == 4 && strncmp(buffer, "SDDS", 4) == 0) {
      fclose(fp);
      return -1;
    }
    fclose(fp);
  }
  return i;
}

UnpackFopen()

FILE * UnpackFopen	(	char *	filename,
		unsigned long	mode,
		short *	popenUsed,
		char **	tmpFileUsed )

Opens a file, potentially unpacking it based on its extension and mode.

This function attempts to open a file, determining whether it needs to be unpacked based on its extension. If unpacking is required and specified by the mode, it either uses a pipe or creates a temporary file to access the unpacked data.

Parameters

filename	The name of the file to open.
mode	Flags indicating unpacking requirements and options.
popenUsed	Pointer to a short that will be set to 1 if popen is used, otherwise 0 (optional).
tmpFileUsed	Pointer to store the name of the temporary file used for unpacking (optional).

Returns

A FILE pointer to the opened file, or NULL if the file could not be opened or an error occurred.

Definition at line 93 of file unpack.c.

                                                                                            {
  static char *command = NULL;
  long type;
  char *tmpName;
 
  if (popenUsed)
    *popenUsed = 0;
  if (tmpFileUsed)
    *tmpFileUsed = NULL;
  if (!filename)
    return NULL;
  if ((type = PackSuffixType(filename, NULL, mode)) < 0)
    return fopen(filename, FOPEN_READ_MODE);
 
  if (!(command = trealloc(command, sizeof(*command) * (strlen(filename) + 100))))
    return NULL;
  if (mode & UNPACK_USE_PIPE) {
    sprintf(command, unpackCommand[type], filename);
    if (popenUsed)
      *popenUsed = 1;
#if defined(vxWorks)
    fprintf(stderr, "popen is not supported in vxWorks\n");
    exit(1);
    return NULL;
#else
    return popen(command, FOPEN_READ_MODE);
#endif
  } else {
    sprintf(command, unpackCommand[type], filename);
    tmpName = tmpname(NULL);
    strcat(command, "> /tmp/");
    strcat(command, tmpName);
    system(command);
 
    sprintf(command, "/tmp/%s", tmpName);
    if (tmpFileUsed)
      cp_str(tmpFileUsed, command);
 
    return fopen(command, FOPEN_READ_MODE);
  }
}

Variable Documentation

unpackCommand

char* unpackCommand[UNPACK_TYPES]

static

Initial value:

= {
  "gzip -dcn %s 2> /dev/null ",
  "freeze -dc %s ",
  "uncompress -c %s ",
}

Definition at line 29 of file unpack.c.

                                           {
  "gzip -dcn %s 2> /dev/null ",
  "freeze -dc %s ",
  "uncompress -c %s ",
};

unpackSuffix

char* unpackSuffix[UNPACK_TYPES]

static

Initial value:

= {
  "gz",
  "F",
  "Z",
}

Definition at line 24 of file unpack.c.

                                          {
  "gz",
  "F",
  "Z",
};