diff options
-rw-r--r-- | configure.ac | 5 | ||||
-rw-r--r-- | file.c | 51 | ||||
-rw-r--r-- | internal/process.h | 6 | ||||
-rw-r--r-- | process.c | 266 |
4 files changed, 311 insertions, 17 deletions
diff --git a/configure.ac b/configure.ac index a33caa5367..ac082a8049 100644 --- a/configure.ac +++ b/configure.ac @@ -1902,10 +1902,15 @@ AC_CHECK_FUNCS(getgidx) AC_CHECK_FUNCS(getgrnam) AC_CHECK_FUNCS(getgrnam_r) AC_CHECK_FUNCS(getgroups) +AC_CHECK_FUNCS(getlogin) +AC_CHECK_FUNCS(getlogin_r) AC_CHECK_FUNCS(getpgid) AC_CHECK_FUNCS(getpgrp) AC_CHECK_FUNCS(getpriority) +AC_CHECK_FUNCS(getpwnam) AC_CHECK_FUNCS(getpwnam_r) +AC_CHECK_FUNCS(getpwuid) +AC_CHECK_FUNCS(getpwuid_r) AC_CHECK_FUNCS(getrandom) AC_CHECK_FUNCS(getresgid) AC_CHECK_FUNCS(getresuid) @@ -3603,21 +3603,42 @@ rb_default_home_dir(VALUE result) #if defined HAVE_PWD_H if (!dir) { - const char *login = getlogin(); - if (login) { - struct passwd *pw = getpwnam(login); - if (pw) { - copy_home_path(result, pw->pw_dir); - endpwent(); - return result; - } - endpwent(); - rb_raise(rb_eArgError, "couldn't find HOME for login `%s' -- expanding `~'", - login); - } - else { - rb_raise(rb_eArgError, "couldn't find login name -- expanding `~'"); - } + /* We'll look up the user's default home dir in the password db by + * login name, if possible, and failing that will fall back to looking + * the information up by uid (as would be needed for processes that + * are not a descendant of login(1) or a work-alike). + * + * While the lookup by uid is more likely to succeed (since we always + * have a uid, but may or may not have a login name), we prefer first + * looking up by name to accommodate the possibility of multiple login + * names (each with its own record in the password database, so each + * with a potentially different home directory) being mapped to the + * same uid (as explicitly allowed for by POSIX; see getlogin(3posix)). + */ + VALUE login_name = rb_getlogin(); + +# if !defined(HAVE_GETPWUID_R) && !defined(HAVE_GETPWUID) + /* This is a corner case, but for backward compatibility reasons we + * want to emit this error if neither the lookup by login name nor + * lookup by getuid() has a chance of succeeding. + */ + if (NIL_P(login_name)) { + rb_raise(rb_eArgError, "couldn't find login name -- expanding `~'"); + } +# endif + + VALUE pw_dir = rb_getpwdirnam_for_login(login_name); + if (NIL_P(pw_dir)) { + pw_dir = rb_getpwdiruid(); + if (NIL_P(pw_dir)) { + rb_raise(rb_eArgError, "couldn't find home for uid `%ld'", (long)getuid()); + } + } + + /* found it */ + copy_home_path(result, RSTRING_PTR(pw_dir)); + rb_str_resize(pw_dir, 0); + return result; } #endif if (!dir) { diff --git a/internal/process.h b/internal/process.h index 5983204d1e..904c9a5cea 100644 --- a/internal/process.h +++ b/internal/process.h @@ -79,6 +79,12 @@ void rb_last_status_clear(void); static inline char **ARGVSTR2ARGV(VALUE argv_str); static inline size_t ARGVSTR2ARGC(VALUE argv_str); +#ifdef HAVE_PWD_H +VALUE rb_getlogin(void); +VALUE rb_getpwdirnam_for_login(VALUE login); /* read as: "get pwd db home dir by username for login" */ +VALUE rb_getpwdiruid(void); /* read as: "get pwd db home dir for getuid()" */ +#endif + RUBY_SYMBOL_EXPORT_BEGIN /* process.c (export) */ int rb_exec_async_signal_safe(const struct rb_execarg *e, char *errmsg, size_t errmsg_buflen); @@ -179,12 +179,40 @@ static int exec_async_signal_safe(const struct rb_execarg *, char *, size_t); #define p_gid_from_name p_gid_from_name #endif +#if defined(HAVE_UNISTD_H) +# if defined(HAVE_GETLOGIN_R) +# define USE_GETLOGIN_R 1 +# define GETLOGIN_R_SIZE_DEFAULT 0x100 +# define GETLOGIN_R_SIZE_LIMIT 0x1000 +# if defined(_SC_LOGIN_NAME_MAX) +# define GETLOGIN_R_SIZE_INIT sysconf(_SC_LOGIN_NAME_MAX) +# else +# define GETLOGIN_R_SIZE_INIT GETLOGIN_R_SIZE_DEFAULT +# endif +# elif defined(HAVE_GETLOGIN) +# define USE_GETLOGIN 1 +# endif +#endif + #if defined(HAVE_PWD_H) -# if defined(HAVE_GETPWNAM_R) && defined(_SC_GETPW_R_SIZE_MAX) +# if defined(HAVE_GETPWUID_R) +# define USE_GETPWUID_R 1 +# elif defined(HAVE_GETPWUID) +# define USE_GETPWUID 1 +# endif +# if defined(HAVE_GETPWNAM_R) # define USE_GETPWNAM_R 1 -# define GETPW_R_SIZE_INIT sysconf(_SC_GETPW_R_SIZE_MAX) +# elif defined(HAVE_GETPWNAM) +# define USE_GETPWNAM 1 +# endif +# if defined(HAVE_GETPWNAM_R) || defined(HAVE_GETPWUID_R) # define GETPW_R_SIZE_DEFAULT 0x1000 # define GETPW_R_SIZE_LIMIT 0x10000 +# if defined(_SC_GETPW_R_SIZE_MAX) +# define GETPW_R_SIZE_INIT sysconf(_SC_GETPW_R_SIZE_MAX) +# else +# define GETPW_R_SIZE_INIT GETPW_R_SIZE_DEFAULT +# endif # endif # ifdef USE_GETPWNAM_R # define PREPARE_GETPWNAM \ @@ -5531,6 +5559,240 @@ check_gid_switch(void) } +#if defined(HAVE_PWD_H) +/** + * Best-effort attempt to obtain the name of the login user, if any, + * associated with the process. Processes not descended from login(1) (or + * similar) may not have a logged-in user; returns Qnil in that case. + */ +VALUE +rb_getlogin(void) +{ +#if ( !defined(USE_GETLOGIN_R) && !defined(USE_GETLOGIN) ) + return Qnil; +#else + char MAYBE_UNUSED(*login) = NULL; + +# ifdef USE_GETLOGIN_R + + long loginsize = GETLOGIN_R_SIZE_INIT; /* maybe -1 */ + + if (loginsize < 0) + loginsize = GETLOGIN_R_SIZE_DEFAULT; + + VALUE maybe_result = rb_str_buf_new(loginsize); + + login = RSTRING_PTR(maybe_result); + loginsize = rb_str_capacity(maybe_result); + rb_str_set_len(maybe_result, loginsize); + + int gle; + errno = 0; + while ((gle = getlogin_r(login, loginsize)) != 0) { + + if (gle == ENOTTY || gle == ENXIO || gle == ENOENT) { + rb_str_resize(maybe_result, 0); + return Qnil; + } + + if (gle != ERANGE || loginsize >= GETLOGIN_R_SIZE_LIMIT) { + rb_str_resize(maybe_result, 0); + rb_syserr_fail(gle, "getlogin_r"); + } + + rb_str_modify_expand(maybe_result, loginsize); + login = RSTRING_PTR(maybe_result); + loginsize = rb_str_capacity(maybe_result); + } + + if (login == NULL) { + rb_str_resize(maybe_result, 0); + return Qnil; + } + + return maybe_result; + +# elif USE_GETLOGIN + + errno = 0; + login = getlogin(); + if (errno) { + if (errno == ENOTTY || errno == ENXIO || errno == ENOENT) { + return Qnil; + } + rb_syserr_fail(errno, "getlogin"); + } + + return login ? rb_str_new_cstr(login) : Qnil; +# endif + +#endif +} + +VALUE +rb_getpwdirnam_for_login(VALUE login_name) +{ +#if ( !defined(USE_GETPWNAM_R) && !defined(USE_GETPWNAM) ) + return Qnil; +#else + + if (NIL_P(login_name)) { + /* nothing to do; no name with which to query the password database */ + return Qnil; + } + + char *login = RSTRING_PTR(login_name); + + struct passwd *pwptr; + +# ifdef USE_GETPWNAM_R + + struct passwd pwdnm; + char *bufnm; + long bufsizenm = GETPW_R_SIZE_INIT; /* maybe -1 */ + + if (bufsizenm < 0) + bufsizenm = GETPW_R_SIZE_DEFAULT; + + VALUE getpwnm_tmp = rb_str_tmp_new(bufsizenm); + + bufnm = RSTRING_PTR(getpwnm_tmp); + bufsizenm = rb_str_capacity(getpwnm_tmp); + rb_str_set_len(getpwnm_tmp, bufsizenm); + + int enm; + errno = 0; + while ((enm = getpwnam_r(login, &pwdnm, bufnm, bufsizenm, &pwptr)) != 0) { + + if (enm == ENOENT || enm== ESRCH || enm == EBADF || enm == EPERM) { + /* not found; non-errors */ + rb_str_resize(getpwnm_tmp, 0); + return Qnil; + } + + if (enm != ERANGE || bufsizenm >= GETPW_R_SIZE_LIMIT) { + rb_str_resize(getpwnm_tmp, 0); + rb_syserr_fail(enm, "getpwnam_r"); + } + + rb_str_modify_expand(getpwnm_tmp, bufsizenm); + bufnm = RSTRING_PTR(getpwnm_tmp); + bufsizenm = rb_str_capacity(getpwnm_tmp); + } + + if (pwptr == NULL) { + /* no record in the password database for the login name */ + rb_str_resize(getpwnm_tmp, 0); + return Qnil; + } + + /* found it */ + VALUE result = rb_str_new_cstr(pwptr->pw_dir); + rb_str_resize(getpwnm_tmp, 0); + return result; + +# elif USE_GETPWNAM + + errno = 0; + pwptr = getpwnam(login); + if (pwptr) { + /* found it */ + return rb_str_new_cstr(pwptr->pw_dir); + } + if (errno + /* avoid treating as errors errno values that indicate "not found" */ + && ( errno != ENOENT && errno != ESRCH && errno != EBADF && errno != EPERM)) { + rb_syserr_fail(errno, "getpwnam"); + } + + return Qnil; /* not found */ +# endif + +#endif +} + +/** + * Look up the user's dflt home dir in the password db, by uid. + */ +VALUE +rb_getpwdiruid(void) +{ +# if !defined(USE_GETPWUID_R) && !defined(USE_GETPWUID) + /* Should never happen... </famous-last-words> */ + return Qnil; +# else + uid_t ruid = getuid(); + + struct passwd *pwptr; + +# ifdef USE_GETPWUID_R + + struct passwd pwdid; + char *bufid; + long bufsizeid = GETPW_R_SIZE_INIT; /* maybe -1 */ + + if (bufsizeid < 0) + bufsizeid = GETPW_R_SIZE_DEFAULT; + + VALUE getpwid_tmp = rb_str_tmp_new(bufsizeid); + + bufid = RSTRING_PTR(getpwid_tmp); + bufsizeid = rb_str_capacity(getpwid_tmp); + rb_str_set_len(getpwid_tmp, bufsizeid); + + int eid; + errno = 0; + while ((eid = getpwuid_r(ruid, &pwdid, bufid, bufsizeid, &pwptr)) != 0) { + + if (eid == ENOENT || eid== ESRCH || eid == EBADF || eid == EPERM) { + /* not found; non-errors */ + rb_str_resize(getpwid_tmp, 0); + return Qnil; + } + + if (eid != ERANGE || bufsizeid >= GETPW_R_SIZE_LIMIT) { + rb_str_resize(getpwid_tmp, 0); + rb_syserr_fail(eid, "getpwuid_r"); + } + + rb_str_modify_expand(getpwid_tmp, bufsizeid); + bufid = RSTRING_PTR(getpwid_tmp); + bufsizeid = rb_str_capacity(getpwid_tmp); + } + + if (pwptr == NULL) { + /* no record in the password database for the uid */ + rb_str_resize(getpwid_tmp, 0); + return Qnil; + } + + /* found it */ + VALUE result = rb_str_new_cstr(pwptr->pw_dir); + rb_str_resize(getpwid_tmp, 0); + return result; + +# elif defined(USE_GETPWUID) + + errno = 0; + pwptr = getpwuid(ruid); + if (pwptr) { + /* found it */ + return rb_str_new_cstr(pwptr->pw_dir); + } + if (errno + /* avoid treating as errors errno values that indicate "not found" */ + && ( errno == ENOENT || errno == ESRCH || errno == EBADF || errno == EPERM)) { + rb_syserr_fail(errno, "getpwuid"); + } + + return Qnil; /* not found */ +# endif + +#endif /* !defined(USE_GETPWUID_R) && !defined(USE_GETPWUID) */ +} +#endif /* HAVE_PWD_H */ + + /********************************************************************* * Document-class: Process::Sys * |