[lvm-devel] [PATCH] Fix building on musl libc

[Zdenek Kabelac]

Dne 5.6.2016 v 21:31 Kylie McClain napsal(a):
> On Mon, May 30, 2016 at 4:55 PM, Kylie McClain <somasissounds at gmail.com> wrote:
>> From: Kylie McClain <somasis at exherbo.org>
>>
>> This patch fixes building and using lvm2 on musl libc. These are taken from
>> Alpine Linux, with permission to submit upstream from Natanael Copa <ncopa at alpinelinux.org>.
>> ---
>>  lib/commands/toolcontext.c | 22 +++++++++++-----------
>>  lib/mm/memlock.c           |  2 +-
>>  tools/lvmcmdline.c         |  6 +++---
>>  3 files changed, 15 insertions(+), 15 deletions(-)
>>
>> diff --git a/lib/commands/toolcontext.c b/lib/commands/toolcontext.c
>> index 1e3f14a..5c6a030 100644
>> --- a/lib/commands/toolcontext.c
>> +++ b/lib/commands/toolcontext.c
>> @@ -1645,7 +1645,10 @@ static void _init_globals(struct cmd_context *cmd)
>>  /*
>>   * Close and reopen stream on file descriptor fd.
>>   */
>> -static int _reopen_stream(FILE *stream, int fd, const char *mode, const char *name, FILE **new_stream)
>> +#ifdef __GLIBC__
>> +#define _reopen_stream(stream, fd, mode, name) __reopen_stream(stream, fd, mode, name, &stream)
>> +
>> +static int __reopen_stream(FILE *stream, int fd, const char *mode, const char *name, FILE **new_stream)
>>  {
>>         int fd_copy, new_fd;
>>
>> @@ -1672,6 +1675,9 @@ static int _reopen_stream(FILE *stream, int fd, const char *mode, const char *na
>>
>>         return 1;
>>  }
>> +#else
>> +#define _reopen_stream(stream, fd, mode, name) (freopen(NULL, mode, stream) != NULL)
>> +#endif
>>
>>  /*
>>   * init_connections();
>> @@ -1828,7 +1834,6 @@ struct cmd_context *create_toolcontext(unsigned is_long_lived,
>>                                        unsigned set_filters)
>>  {
>>         struct cmd_context *cmd;
>> -       FILE *new_stream;
>>         int flags;
>>
>>  #ifdef M_MMAP_MAX
>> @@ -1878,9 +1883,8 @@ struct cmd_context *create_toolcontext(unsigned is_long_lived,
>>                 if (is_valid_fd(STDIN_FILENO) &&
>>                     ((flags = fcntl(STDIN_FILENO, F_GETFL)) > 0) &&
>>                     (flags & O_ACCMODE) != O_WRONLY) {
>> -                       if (!_reopen_stream(stdin, STDIN_FILENO, "r", "stdin", &new_stream))
>> +                       if (!_reopen_stream(stdin, STDIN_FILENO, "r", "stdin"))
>>                                 goto_out;
>> -                       stdin = new_stream;
>>                         if (setvbuf(stdin, cmd->linebuffer, _IOLBF, linebuffer_size)) {
>>                                 log_sys_error("setvbuf", "");
>>                                 goto out;
>> @@ -1890,9 +1894,8 @@ struct cmd_context *create_toolcontext(unsigned is_long_lived,
>>                 if (is_valid_fd(STDOUT_FILENO) &&
>>                     ((flags = fcntl(STDOUT_FILENO, F_GETFL)) > 0) &&
>>                     (flags & O_ACCMODE) != O_RDONLY) {
>> -                       if (!_reopen_stream(stdout, STDOUT_FILENO, "w", "stdout", &new_stream))
>> +                       if (!_reopen_stream(stdout, STDOUT_FILENO, "w", "stdout"))
>>                                 goto_out;
>> -                       stdout = new_stream;
>>                         if (setvbuf(stdout, cmd->linebuffer + linebuffer_size,
>>                                      _IOLBF, linebuffer_size)) {
>>                                 log_sys_error("setvbuf", "");
>> @@ -2218,7 +2221,6 @@ int refresh_toolcontext(struct cmd_context *cmd)
>>  void destroy_toolcontext(struct cmd_context *cmd)
>>  {
>>         struct dm_config_tree *cft_cmdline;
>> -       FILE *new_stream;
>>         int flags;
>>
>>         if (cmd->dump_filter && cmd->filter && cmd->filter->dump &&
>> @@ -2254,8 +2256,7 @@ void destroy_toolcontext(struct cmd_context *cmd)
>>                 if (is_valid_fd(STDIN_FILENO) &&
>>                     ((flags = fcntl(STDIN_FILENO, F_GETFL)) > 0) &&
>>                     (flags & O_ACCMODE) != O_WRONLY) {
>> -                       if (_reopen_stream(stdin, STDIN_FILENO, "r", "stdin", &new_stream)) {
>> -                               stdin = new_stream;
>> +                       if (_reopen_stream(stdin, STDIN_FILENO, "r", "stdin")) {
>>                                 setlinebuf(stdin);
>>                         } else
>>                                 cmd->linebuffer = NULL; /* Leave buffer in place (deliberate leak) */
>> @@ -2264,8 +2265,7 @@ void destroy_toolcontext(struct cmd_context *cmd)
>>                 if (is_valid_fd(STDOUT_FILENO) &&
>>                     ((flags = fcntl(STDOUT_FILENO, F_GETFL)) > 0) &&
>>                     (flags & O_ACCMODE) != O_RDONLY) {
>> -                       if (_reopen_stream(stdout, STDOUT_FILENO, "w", "stdout", &new_stream)) {
>> -                               stdout = new_stream;
>> +                       if (_reopen_stream(stdout, STDOUT_FILENO, "w", "stdout")) {
>>                                 setlinebuf(stdout);
>>                         } else
>>                                 cmd->linebuffer = NULL; /* Leave buffer in place (deliberate leak) */
>> diff --git a/lib/mm/memlock.c b/lib/mm/memlock.c
>> index 851cd33..1a1915b 100644
>> --- a/lib/mm/memlock.c
>> +++ b/lib/mm/memlock.c
>> @@ -145,7 +145,7 @@ static void _touch_memory(void *mem, size_t size)
>>
>>  static void _allocate_memory(void)
>>  {
>> -#ifndef VALGRIND_POOL
>> +#if !defined(VALGRIND_POOL) && defined(__GLIBC__)
>>         void *stack_mem;
>>         struct rlimit limit;
>>         int i, area = 0, missing = _size_malloc_tmp, max_areas = 32, hblks;
>> diff --git a/tools/lvmcmdline.c b/tools/lvmcmdline.c
>> index be6821b..2095fbe 100644
>> --- a/tools/lvmcmdline.c
>> +++ b/tools/lvmcmdline.c
>> @@ -1798,7 +1798,7 @@ static int _check_standard_fds(void)
>>         int err = is_valid_fd(STDERR_FILENO);
>>
>>         if (!is_valid_fd(STDIN_FILENO) &&
>> -           !(stdin = fopen(_PATH_DEVNULL, "r"))) {
>> +           !freopen(_PATH_DEVNULL, "r", stdin)) {
>>                 if (err)
>>                         perror("stdin stream open");
>>                 else
>> @@ -1808,7 +1808,7 @@ static int _check_standard_fds(void)
>>         }
>>
>>         if (!is_valid_fd(STDOUT_FILENO) &&
>> -           !(stdout = fopen(_PATH_DEVNULL, "w"))) {
>> +           !freopen(_PATH_DEVNULL, "w", stdout)) {
>>                 if (err)
>>                         perror("stdout stream open");
>>                 /* else no stdout */
>> @@ -1816,7 +1816,7 @@ static int _check_standard_fds(void)
>>         }
>>
>>         if (!is_valid_fd(STDERR_FILENO) &&
>> -           !(stderr = fopen(_PATH_DEVNULL, "w"))) {
>> +           !freopen(_PATH_DEVNULL, "w", stderr)) {

Hi

Why do you call here 'freopen()' when descriptor is not valid,
thus plain 'fopen()' is correct ?

Regards

Zdenek