From a5fcf0e3e491ede0d03e71f064e8e6d24e889aab Mon Sep 17 00:00:00 2001 From: Daniel Henrique Barboza Date: Thu, 21 Jun 2018 07:21:49 -0300 Subject: qga: bios_supports_mode: decoupling pm-utils and sys logic In bios_supports_mode there is a verification to assert if the chosen suspend mode is supported by the pmutils tools and, if not, we see if the Linux sys state files supports it. This verification is done in the same function, one after the other, and it works for now. But, when adding a new suspend mechanism that will not necessarily follow the same return 0 or 1 logic of pmutils, this code will be hard to deal with. This patch decouple the two existing logics into their own functions, pmutils_supports_mode and linux_sys_state_supports_mode, which in turn are used inside bios_support_mode. The existing logic is kept but now it's easier to extend it. Signed-off-by: Daniel Henrique Barboza Signed-off-by: Michael Roth --- qga/commands-posix.c | 116 ++++++++++++++++++++++++++++++--------------------- 1 file changed, 68 insertions(+), 48 deletions(-) (limited to 'qga/commands-posix.c') diff --git a/qga/commands-posix.c b/qga/commands-posix.c index bd2c3514d8..a8299ecc77 100644 --- a/qga/commands-posix.c +++ b/qga/commands-posix.c @@ -1478,75 +1478,43 @@ qmp_guest_fstrim(bool has_minimum, int64_t minimum, Error **errp) #define SUSPEND_MODE_RAM 2 #define SUSPEND_MODE_HYBRID 3 -static void bios_supports_mode(int suspend_mode, Error **errp) +static bool pmutils_supports_mode(int suspend_mode, Error **errp) { Error *local_err = NULL; - const char *pmutils_arg, *sysfile_str; + const char *pmutils_arg; const char *pmutils_bin = "pm-is-supported"; char *pmutils_path; pid_t pid; int status; + bool ret = false; switch (suspend_mode) { case SUSPEND_MODE_DISK: pmutils_arg = "--hibernate"; - sysfile_str = "disk"; break; case SUSPEND_MODE_RAM: pmutils_arg = "--suspend"; - sysfile_str = "mem"; break; case SUSPEND_MODE_HYBRID: pmutils_arg = "--suspend-hybrid"; - sysfile_str = NULL; break; default: - error_setg(errp, "guest suspend mode not supported"); - return; + return ret; } pmutils_path = g_find_program_in_path(pmutils_bin); + if (!pmutils_path) { + return ret; + } pid = fork(); if (!pid) { - char buf[32]; /* hopefully big enough */ - ssize_t ret; - int fd; - setsid(); - reopen_fd_to_null(0); - reopen_fd_to_null(1); - reopen_fd_to_null(2); - - if (pmutils_path) { - execle(pmutils_path, pmutils_bin, pmutils_arg, NULL, environ); - } - + execle(pmutils_path, pmutils_bin, pmutils_arg, NULL, environ); /* - * If we get here either pm-utils is not installed or execle() has - * failed. Let's try the manual method if the caller wants it. + * If we get here execle() has failed. */ - - if (!sysfile_str) { - _exit(SUSPEND_NOT_SUPPORTED); - } - - fd = open(LINUX_SYS_STATE_FILE, O_RDONLY); - if (fd < 0) { - _exit(SUSPEND_NOT_SUPPORTED); - } - - ret = read(fd, buf, sizeof(buf)-1); - if (ret <= 0) { - _exit(SUSPEND_NOT_SUPPORTED); - } - buf[ret] = '\0'; - - if (strstr(buf, sysfile_str)) { - _exit(SUSPEND_SUPPORTED); - } - _exit(SUSPEND_NOT_SUPPORTED); } else if (pid < 0) { error_setg_errno(errp, errno, "failed to create child process"); @@ -1559,17 +1527,11 @@ static void bios_supports_mode(int suspend_mode, Error **errp) goto out; } - if (!WIFEXITED(status)) { - error_setg(errp, "child process has terminated abnormally"); - goto out; - } - switch (WEXITSTATUS(status)) { case SUSPEND_SUPPORTED: + ret = true; goto out; case SUSPEND_NOT_SUPPORTED: - error_setg(errp, - "the requested suspend mode is not supported by the guest"); goto out; default: error_setg(errp, @@ -1580,6 +1542,64 @@ static void bios_supports_mode(int suspend_mode, Error **errp) out: g_free(pmutils_path); + return ret; +} + +static bool linux_sys_state_supports_mode(int suspend_mode, Error **errp) +{ + const char *sysfile_str; + char buf[32]; /* hopefully big enough */ + int fd; + ssize_t ret; + + switch (suspend_mode) { + + case SUSPEND_MODE_DISK: + sysfile_str = "disk"; + break; + case SUSPEND_MODE_RAM: + sysfile_str = "mem"; + break; + default: + return false; + } + + fd = open(LINUX_SYS_STATE_FILE, O_RDONLY); + if (fd < 0) { + return false; + } + + ret = read(fd, buf, sizeof(buf) - 1); + if (ret <= 0) { + return false; + } + buf[ret] = '\0'; + + if (strstr(buf, sysfile_str)) { + return true; + } + return false; +} + +static void bios_supports_mode(int suspend_mode, Error **errp) +{ + Error *local_err = NULL; + bool ret; + + ret = pmutils_supports_mode(suspend_mode, &local_err); + if (ret) { + return; + } + if (local_err) { + error_propagate(errp, local_err); + return; + } + ret = linux_sys_state_supports_mode(suspend_mode, errp); + if (!ret) { + error_setg(errp, + "the requested suspend mode is not supported by the guest"); + return; + } } static void guest_suspend(int suspend_mode, Error **errp) -- cgit v1.2.3