diff --git a/alsapid/alsapid.h b/alsapid/alsapid.h new file mode 100644 index 00000000..7e89d15a --- /dev/null +++ b/alsapid/alsapid.h @@ -0,0 +1,33 @@ +/* -*- Mode: C ; c-basic-offset: 2 -*- */ +/* + * LADI Session Handler (ladish) + * + * Copyright (C) 2010 Nedko Arnaudov + * + ************************************************************************** + * This file contains interface to alsapid functionality + ************************************************************************** + * + * LADI Session Handler is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * LADI Session Handler is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with LADI Session Handler. If not, see + * or write to the Free Software Foundation, Inc., + * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. + */ + +#ifndef ALSAPID_H__0A27F284_7538_4791_8023_0FBED929EAF3__INCLUDED +#define ALSAPID_H__0A27F284_7538_4791_8023_0FBED929EAF3__INCLUDED + +void alsapid_compose_src_link(int alsa_client_id, char * buffer); +void alsapid_compose_dst_link(char * buffer); + +#endif /* #ifndef ALSAPID_H__0A27F284_7538_4791_8023_0FBED929EAF3__INCLUDED */ diff --git a/alsapid/asound.versions b/alsapid/asound.versions new file mode 100644 index 00000000..e5b1b101 --- /dev/null +++ b/alsapid/asound.versions @@ -0,0 +1,16 @@ +ALSA_0.9 { + global: + snd_*; + + _snd_*_open; + _snd_*_dlsym_*; + _snd_*_poll_descriptor; + _snd_pcm_hook_*; + + __snd_pcm_hw_params_*; + __snd_pcm_sw_params_*; + __snd_*_dlsym_*; + + local: + *; +}; diff --git a/alsapid/helper.c b/alsapid/helper.c new file mode 100644 index 00000000..75c25990 --- /dev/null +++ b/alsapid/helper.c @@ -0,0 +1,42 @@ +/* -*- Mode: C ; c-basic-offset: 2 -*- */ +/* + * LADI Session Handler (ladish) + * + * Copyright (C) 2010 Nedko Arnaudov + * + ************************************************************************** + * This file contains alsapid helper functionality + ************************************************************************** + * + * LADI Session Handler is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * LADI Session Handler is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with LADI Session Handler. If not, see + * or write to the Free Software Foundation, Inc., + * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. + */ + +#include +#include +#include + +#include "alsapid.h" + +void alsapid_compose_src_link(int alsa_client_id, char * buffer) +{ + sprintf(buffer, "/tmp/alsapid-%lld-%d", (long long)getuid(), alsa_client_id); +} + +void alsapid_compose_dst_link(char * buffer) +{ + sprintf(buffer, "/proc/%lld", (long long)getpid()); +} + diff --git a/alsapid/lib.c b/alsapid/lib.c new file mode 100644 index 00000000..86db33f5 --- /dev/null +++ b/alsapid/lib.c @@ -0,0 +1,170 @@ +/* -*- Mode: C ; c-basic-offset: 2 -*- */ +/* + * LADI Session Handler (ladish) + * + * Copyright (C) 2010 Nedko Arnaudov + * + ************************************************************************** + * This file contains implementation of the libasound LD_PRELOAD-ed alsapid library + ************************************************************************** + * + * LADI Session Handler is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * LADI Session Handler is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with LADI Session Handler. If not, see + * or write to the Free Software Foundation, Inc., + * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. + */ + +#define _GNU_SOURCE + +#include +#include +#include +#include + +#include "alsapid.h" + +#define API_VERSION "ALSA_0.9" + +// gcc -g -shared -Wl,--version-script=asound.versions -o libasound.so -fPIC -ldl -Wall -Werror lib.c helper.c +// LD_LIBRARY_PATH=alsapid LD_PRELOAD=libasound.so seq24 + +static void create_symlink(int alsa_client_id) +{ + char src[PATH_MAX]; + char dst[PATH_MAX]; + + alsapid_compose_src_link(alsa_client_id, src); + alsapid_compose_dst_link(dst); + + //printf("'%s' -> '%s'\n", src, dst); + if (symlink(dst, src) != 0) + { + fprintf(stderr, "symlink(\"%s\", \"%s\") failed with %d (%s)", dst, src, errno, strerror(errno)); + } +} + +static void destroy_symlink(int alsa_client_id) +{ + char src[PATH_MAX]; + + alsapid_compose_src_link(alsa_client_id, src); + + //printf("'%s'\n", src); + if (unlink(src) != 0) + { + fprintf(stderr, "unlink(\"%s\") failed with %d (%s)", src, errno, strerror(errno)); + } +} + +//static int (* real_snd_seq_open)(snd_seq_t ** handle, const char * name, int streams, int mode); +static int (* real_snd_seq_set_client_name)(snd_seq_t * seq, const char * name); +static int (* real_snd_seq_close)(snd_seq_t * handle); +//static int (* real_snd_seq_create_port)(snd_seq_t * handle, snd_seq_port_info_t * info); +//static int (* real_snd_seq_create_simple_port)(snd_seq_t * seq, const char * name, unsigned int caps, unsigned int type); + +void __attribute__ ((constructor)) init(void); + +/* Library constructor */ +void init(void) +{ +// real_snd_seq_open = dlvsym(RTLD_NEXT, "snd_seq_open", API_VERSION); + real_snd_seq_set_client_name = dlvsym(RTLD_NEXT, "snd_seq_set_client_name", API_VERSION); + real_snd_seq_close = dlvsym(RTLD_NEXT, "snd_seq_close", API_VERSION); +// real_snd_seq_create_port = dlvsym(RTLD_NEXT, "snd_seq_create_port", API_VERSION); +// real_snd_seq_create_simple_port = dlvsym(RTLD_NEXT, "snd_seq_create_simple_port", API_VERSION); +} + +#define CHECK_FUNC(func) \ + if (real_ ## func == NULL) \ + { \ + fprintf(stderr, "dlvsym(\"" #func "\", \""API_VERSION"\") failed.\n"); \ + return -1; \ + } + +#if 0 +int snd_seq_open(snd_seq_t ** handle, const char * name, int streams, int mode) +{ + int ret; + + //printf("Attempt to create alsa client '%s', %d streams and mode %d\n", name, streams, mode); + + CHECK_FUNC(snd_seq_open); + + //printf("real_snd_seq_open = %p\n", real_snd_seq_open); + ret = real_snd_seq_open(handle, name, streams, mode); + if (ret == 0) + { + //printf("alsa client %p (%d) created\n", *handle, snd_seq_client_id(*handle)); + } + return ret; +} +#endif + +int snd_seq_set_client_name(snd_seq_t * seq, const char * name) +{ + int ret; + + //printf("Attempt to set alsa client name to '%s' of %p\n", name, seq); getchar(); + + CHECK_FUNC(snd_seq_set_client_name); + + ret = real_snd_seq_set_client_name(seq, name); + + //printf("name set?\n"); getchar(); + + if (ret == 0) + { + //printf("ALSAPID: pid = %lld SETNAME %d '%s'\n", (long long)getpid(), snd_seq_client_id(seq), name); + create_symlink(snd_seq_client_id(seq)); + } + + return ret; +} + +int snd_seq_close(snd_seq_t * handle) +{ + CHECK_FUNC(snd_seq_close); + + //printf("ALSAPID: pid = %lld CLOSE %d\n", (long long)getpid(), snd_seq_client_id(handle)); + destroy_symlink(snd_seq_client_id(handle)); + + return real_snd_seq_close(handle); +} + +#if 0 +int snd_seq_create_port(snd_seq_t * handle, snd_seq_port_info_t * info) +{ + int ret; + + CHECK_FUNC(snd_seq_create_port); + + ret = real_snd_seq_create_port(handle, info); + + //printf("port created?\n"); getchar(); + + return ret; +} + +int snd_seq_create_simple_port(snd_seq_t * seq, const char * name, unsigned int caps, unsigned int type) +{ + int ret; + + CHECK_FUNC(snd_seq_create_simple_port); + + ret = real_snd_seq_create_simple_port(seq, name, caps, type); + + //printf("simple port created?\n"); getchar(); + + return ret; +} +#endif