[lttng-tools.git] / src / lib / lttng-ctl / filter / memstream.h

#ifndef _LTTNG_CTL_MEMSTREAM_H
#define _LTTNG_CTL_MEMSTREAM_H

/*
 * src/lib/lttng-ctl/memstream.h
 *
 * Copyright 2012 (c) - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
 *
 * memstream compatibility layer.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 */

#ifdef LTTNG_HAVE_FMEMOPEN
#include <stdio.h>

static inline
FILE *lttng_fmemopen(void *buf, size_t size, const char *mode)
{
	return fmemopen(buf, size, mode);
}

#else /* LTTNG_HAVE_FMEMOPEN */

#include <stdlib.h>
#include <stdio.h>
#include <common/error.h>

/*
 * Fallback for systems which don't have fmemopen. Copy buffer to a
 * temporary file, and use that file as FILE * input.
 */
static inline
FILE *lttng_fmemopen(void *buf, size_t size, const char *mode)
{
	char tmpname[PATH_MAX];
	size_t len;
	FILE *fp;
	int ret;

	/*
	 * Support reading only.
	 */
	if (strcmp(mode, "rb") != 0) {
		return NULL;
	}
	strncpy(tmpname, "/tmp/lttng-tmp-XXXXXX", PATH_MAX);
	ret = mkstemp(tmpname);
	if (ret < 0) {
		return NULL;
	}
	/*
	 * We need to write to the file.
	 */
	fp = fdopen(ret, "w+");
	if (!fp) {
		goto error_unlink;
	}
	/* Copy the entire buffer to the file */
	len = fwrite(buf, sizeof(char), size, fp);
	if (len != size) {
		goto error_close;
	}
	ret = fseek(fp, 0L, SEEK_SET);
	if (ret < 0) {
		PERROR("fseek");
		goto error_close;
	}
	/* We keep the handle open, but can unlink the file on the VFS. */
	ret = unlink(tmpname);
	if (ret < 0) {
		PERROR("unlink");
	}
	return fp;

error_close:
	ret = fclose(fp);
	if (ret < 0) {
		PERROR("close");
	}
error_unlink:
	ret = unlink(tmpname);
	if (ret < 0) {
		PERROR("unlink");
	}
	return NULL;
}

#endif /* LTTNG_HAVE_FMEMOPEN */

#endif /* _LTTNG_CTL_MEMSTREAM_H */
Commit	Line	Data
53a80697 MD	1	#ifndef _LTTNG_CTL_MEMSTREAM_H
	2	#define _LTTNG_CTL_MEMSTREAM_H
	3
	4	/*
	5	* src/lib/lttng-ctl/memstream.h
	6	*
	7	* Copyright 2012 (c) - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
	8	*
	9	* memstream compatibility layer.
	10	*
	11	* Permission is hereby granted, free of charge, to any person obtaining a copy
	12	* of this software and associated documentation files (the "Software"), to deal
	13	* in the Software without restriction, including without limitation the rights
	14	* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
	15	* copies of the Software, and to permit persons to whom the Software is
	16	* furnished to do so, subject to the following conditions:
	17	*
	18	* The above copyright notice and this permission notice shall be included in
	19	* all copies or substantial portions of the Software.
	20	*/
	21
53a80697 MD	22	#ifdef LTTNG_HAVE_FMEMOPEN
	23	#include <stdio.h>
	24
	25	static inline
	26	FILE lttng_fmemopen(void buf, size_t size, const char *mode)
	27	{
	28	return fmemopen(buf, size, mode);
	29	}
	30
	31	#else /* LTTNG_HAVE_FMEMOPEN */
	32
	33	#include <stdlib.h>
	34	#include <stdio.h>
9cd8e997	35	#include <common/error.h>
53a80697 MD	36
	37	/*
	38	* Fallback for systems which don't have fmemopen. Copy buffer to a
	39	* temporary file, and use that file as FILE * input.
	40	*/
	41	static inline
	42	FILE lttng_fmemopen(void buf, size_t size, const char *mode)
	43	{
	44	char tmpname[PATH_MAX];
	45	size_t len;
	46	FILE *fp;
	47	int ret;
	48
	49	/*
	50	* Support reading only.
	51	*/
	52	if (strcmp(mode, "rb") != 0) {
	53	return NULL;
	54	}
	55	strncpy(tmpname, "/tmp/lttng-tmp-XXXXXX", PATH_MAX);
	56	ret = mkstemp(tmpname);
	57	if (ret < 0) {
	58	return NULL;
	59	}
	60	/*
	61	* We need to write to the file.
	62	*/
	63	fp = fdopen(ret, "w+");
	64	if (!fp) {
	65	goto error_unlink;
	66	}
	67	/* Copy the entire buffer to the file */
	68	len = fwrite(buf, sizeof(char), size, fp);
	69	if (len != size) {
	70	goto error_close;
	71	}
	72	ret = fseek(fp, 0L, SEEK_SET);
	73	if (ret < 0) {
6f04ed72	74	PERROR("fseek");
53a80697 MD	75	goto error_close;
	76	}
	77	/* We keep the handle open, but can unlink the file on the VFS. */
	78	ret = unlink(tmpname);
	79	if (ret < 0) {
6f04ed72	80	PERROR("unlink");
53a80697 MD	81	}
	82	return fp;
	83
	84	error_close:
	85	ret = fclose(fp);
	86	if (ret < 0) {
6f04ed72	87	PERROR("close");
53a80697 MD	88	}
	89	error_unlink:
	90	ret = unlink(tmpname);
	91	if (ret < 0) {
6f04ed72	92	PERROR("unlink");
53a80697 MD	93	}
	94	return NULL;
	95	}
	96
	97	#endif /* LTTNG_HAVE_FMEMOPEN */
	98
53a80697	99	#endif /* _LTTNG_CTL_MEMSTREAM_H */