[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>

/*
 * 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
	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
	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>
	35
	36	/*
	37	* Fallback for systems which don't have fmemopen. Copy buffer to a
	38	* temporary file, and use that file as FILE * input.
	39	*/
	40	static inline
	41	FILE lttng_fmemopen(void buf, size_t size, const char *mode)
	42	{
	43	char tmpname[PATH_MAX];
	44	size_t len;
	45	FILE *fp;
	46	int ret;
	47
	48	/*
	49	* Support reading only.
	50	*/
	51	if (strcmp(mode, "rb") != 0) {
	52	return NULL;
	53	}
	54	strncpy(tmpname, "/tmp/lttng-tmp-XXXXXX", PATH_MAX);
	55	ret = mkstemp(tmpname);
	56	if (ret < 0) {
	57	return NULL;
	58	}
	59	/*
	60	* We need to write to the file.
	61	*/
	62	fp = fdopen(ret, "w+");
	63	if (!fp) {
	64	goto error_unlink;
	65	}
	66	/* Copy the entire buffer to the file */
	67	len = fwrite(buf, sizeof(char), size, fp);
	68	if (len != size) {
	69	goto error_close;
	70	}
	71	ret = fseek(fp, 0L, SEEK_SET);
	72	if (ret < 0) {
	73	PERROR("fseek");
	74	goto error_close;
	75	}
	76	/* We keep the handle open, but can unlink the file on the VFS. */
	77	ret = unlink(tmpname);
	78	if (ret < 0) {
	79	PERROR("unlink");
	80	}
	81	return fp;
	82
	83	error_close:
	84	ret = fclose(fp);
	85	if (ret < 0) {
	86	PERROR("close");
	87	}
	88	error_unlink:
	89	ret = unlink(tmpname);
	90	if (ret < 0) {
	91	PERROR("unlink");
	92	}
	93	return NULL;
	94	}
	95
	96	#endif /* LTTNG_HAVE_FMEMOPEN */
	97
	98	#endif /* _LTTNG_CTL_MEMSTREAM_H */