tools: acrn-crashlog: command utils for acrn-crashlog

This file provides functions to call system commands.

Signed-off-by: Liu Xinwu <xinwu.liu@intel.com>
Reviewed-by: Zhang Yanmin <yanmin.zhang@intel.com>
Reviewed-by: Liu Chuansheng <chuansheng.liu@intel.com>
Reviewed-by: Zhao Yakui <yakui.zhao@intel.com>
Reviewed-by: Geoffroy Van Cutsem <geoffroy.vancutsem@intel.com>
Acked-by: Eddie Dong <Eddie.dong@intel.com>

tools/acrn-crashlog/common/Makefile

@@ -1,5 +1,6 @@
 objects = log_sys.o \
-	  strutils.o
+	  strutils.o \
+	  cmdutils.o
 
 all: check_obj $(objects)
 check_obj:

tools/acrn-crashlog/common/cmdutils.c

@@ -0,0 +1,232 @@
+/*
+ * Copyright (C) 2018 Intel Corporation
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <unistd.h>
+#include <string.h>
+#include <sys/mman.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <malloc.h>
+#include <errno.h>
+#include <stdarg.h>
+#include <sys/wait.h>
+#include "cmdutils.h"
+#include "strutils.h"
+#include "log_sys.h"
+
+/**
+ * Execute a command described in an array of pointers to null-terminated
+ * strings, and redirect the output to specified file. The file will be
+ * created/truncated if it exists/non-exists. This function will be blocked
+ * until the child process exits.
+ *
+ * @param argv An array of pointers to null-terminated strings that
+ *		represent the argument list available to the new program.
+ *		The array of pointers must be terminated by a null pointer.
+ * @param outfile File to record command's output, NULL means that this
+ *		  function doesn't handle command's output.
+ *
+ * @return If a child process could not be created, or its status could not be
+ *	   retrieved, or it was killed/stopped by signal, the return value
+ *	   is -1.
+ *	   If all system calls succeed, then the return value is the
+ *	   termination status of the child process used to execute command.
+ */
+int execv_out2file(char *argv[], char *outfile)
+{
+	pid_t pid;
+
+	pid = fork();
+	if (pid < 0) {
+		LOGE("fork error (%s)\n", strerror(errno));
+		return -1;
+	}
+
+	if (pid == 0) {
+		int res;
+		int fd;
+
+		if (outfile) {
+			fd = open(outfile, O_WRONLY | O_CREAT | O_TRUNC, 0664);
+			if (fd < 0) {
+				LOGE("open error (%s)\n", strerror(errno));
+				return -1;
+			}
+			res = dup2(fd, STDOUT_FILENO);
+			if (res < 0) {
+				close(fd);
+				LOGE("dup2 error (%s)\n", strerror(errno));
+				return -1;
+			}
+		}
+
+		res = execvp(argv[0], argv);
+		if (res == -1) {
+			LOGE("execvp (%s) failed, error (%s)\n", argv[0],
+			     strerror(errno));
+			return -1;
+		}
+	} else {
+		pid_t res;
+		int status;
+		int exit_status;
+
+		res = waitpid(pid, &status, 0);
+		if (res == -1) {
+			LOGE("waitpid failed, error (%s)\n", strerror(errno));
+			return res;
+		}
+
+		if (WIFEXITED(status)) {
+			exit_status = WEXITSTATUS(status);
+			if (!exit_status)
+				LOGI("%s exited, status=0\n", argv[0]);
+			else
+				LOGE("%s exited, status=%d\n", argv[0],
+				     exit_status);
+			return exit_status;
+		} else if (WIFSIGNALED(status)) {
+			LOGE("%s killed by signal %d\n", argv[0],
+			     WTERMSIG(status));
+		} else if (WIFSTOPPED(status)) {
+			LOGE("%s stopped by signal %d\n", argv[0],
+			     WSTOPSIG(status));
+		}
+
+	}
+
+	return -1;
+}
+
+int debugfs_cmd(char *loop_dev, char *cmd, char *outfile)
+{
+	char *argv[5] = {"debugfs", "-R", NULL, NULL, 0};
+
+	argv[2] = cmd;
+	argv[3] = loop_dev;
+	return  execv_out2file(argv, outfile);
+}
+
+/**
+ * Execute a command described in format string, and redirect the output
+ * to specified file. The file will be created/truncated if it
+ * exists/non-exists. This function will be blocked until the child process
+ * exits.
+ *
+ * @param outfile File to record command's output, NULL means that this
+ *		  function doesn't handle command's output.
+ * @param fmt Format string of command.
+ *
+ * @return If a child process could not be created, or its status could not be
+ *	   retrieved, or it was killed/stopped by signal, the return value
+ *	   is -1.
+ *	   If all system calls succeed, then the return value is the
+ *	   termination status of the child process used to execute command.
+ */
+int exec_out2file(char *outfile, char *fmt, ...)
+{
+	va_list args;
+	char *cmd;
+	char *start;
+	char *p;
+	int ret;
+	int argc;
+	char **argv;
+	int i = 0;
+
+	va_start(args, fmt);
+	ret = vasprintf(&cmd, fmt, args);
+	va_end(args);
+	if (ret < 0)
+		return ret;
+
+	strtrim(cmd);
+	argc = strcnt(cmd, ' ') + 1;
+
+	argv = (char **)calloc(argc + 1, sizeof(char *));
+	if (argv == NULL) {
+		free(cmd);
+		LOGE("calloc failed, error (%s)\n", strerror(errno));
+		return -1;
+	}
+
+	/* string to argv[] */
+	start = cmd;
+	argv[i++] = start;
+	while (start && (p = strchr(start, ' '))) {
+		argv[i++] = p + 1;
+		*p = 0;
+		if (*(p + 1) != '"')
+			start = p + 1;
+		else
+			start = strchr(p + 2, '"');
+	}
+
+	ret = execv_out2file(argv, outfile);
+
+	free(argv);
+	free(cmd);
+
+	return ret;
+}
+
+/**
+ * Execute a command described in format string, and redirect the output
+ * to memory. The memory is allocated by this function and needs to be freed
+ * after return.
+ *
+ * @param fmt Format string of command.
+ *
+ * @return a pointer to command's output if successful, or NULL if not.
+ */
+char *exec_out2mem(char *fmt, ...)
+{
+	va_list args;
+	char *cmd;
+	FILE *pp;
+	char *out = NULL;
+	char *new;
+	char tmp[1024];
+	int memsize = 0;
+	int newlen = 0;
+	int len = 0;
+	int ret;
+
+	va_start(args, fmt);
+	ret = vasprintf(&cmd, fmt, args);
+	va_end(args);
+	if (ret < 0)
+		return NULL;
+
+	pp = popen(cmd, "r");
+	if (!pp)
+		goto free_cmd;
+
+	while (fgets(tmp, 1024, pp) != NULL) {
+		newlen += strlen(tmp);
+		if (newlen + 1 > memsize) {
+			memsize += 1024;
+			new = realloc(out, memsize);
+			if (!new) {
+				if (out)
+					free(out);
+				goto end;
+			} else {
+				out = new;
+			}
+		}
+		memcpy(out + len, tmp, strlen(tmp) + 1);
+
+		len = newlen;
+	}
+
+end:
+	pclose(pp);
+free_cmd:
+	free(cmd);
+
+	return out;
+}

tools/acrn-crashlog/common/include/cmdutils.h

@@ -0,0 +1,9 @@
+/*
+ * Copyright (C) 2018 Intel Corporation
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+int execv_out2file(char *argv[], char *outfile);
+int debugfs_cmd(char *loop_dev, char *cmd, char *outfile);
+int exec_out2file(char *outfile, char *fmt, ...);
+char *exec_out2mem(char *fmt, ...);