Initial commit

3 files changed, 149 insertions, 0 deletions

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..ffa445f
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1 @@
+profile
diff --git a/Makefile b/Makefile
new file mode 100644
index 0000000..7bba597
--- /dev/null
+++ b/Makefile
@@ -0,0 +1,7 @@
+CC=clang
+CFLAGS=-Wall -Wextra -O0 -g
+EXE=profile
+SOURCES=profile.c
+
+all:
+	$(CC) $(CFLAGS) -o $(EXE) $(SOURCES) $(LDFLAGS)
diff --git a/profile.c b/profile.c
new file mode 100644
index 0000000..cfea454
--- /dev/null
+++ b/profile.c
@@ -0,0 +1,141 @@
+/*
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2016 Matias Linares.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+#include <assert.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/resource.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <unistd.h>
+
+void spawn_child(char *progname, char **args, int fd);
+void usage(char *progname);
+
+void usage(char *progname)
+{
+    printf("%s [-o outfile] program arg1 arg2...\n"
+           "\n"
+           "Profile the program passed by parameter with it's arguments.\n"
+           "If the [-o outfile] option is provided, the output of the program\n"
+           "will be stored on output file. Otherwise it won't print any output\n",
+           progname);
+}
+
+void spawn_child(char *progname, char **args, int fd)
+{
+    /* close the files descriptors. */
+    if(fd > 0)
+    {
+        close(STDOUT_FILENO);
+        dup(fd);
+        close(STDERR_FILENO);
+        dup(fd);
+
+        close(fd);
+    }
+    else
+    {
+        close(STDERR_FILENO);
+        close(STDOUT_FILENO);
+    }
+
+    close(STDIN_FILENO);
+
+    if((execvp(progname, args)) == -1)
+    {
+        fprintf(stderr, "%d - %s\n", errno, strerror(errno));
+        exit(1);
+    }
+}
+
+int main(int argc, char **argv)
+{
+    pid_t curpid;
+    int status = -1;
+    char *prog_name = NULL;
+    char **args = NULL;
+    char *out_file = NULL;
+    int offset = 1;
+
+    if(strcmp(argv[1], "-o") == 0)
+    {
+        out_file = (char *) calloc(strlen(argv[2]), sizeof(char));
+        strcpy(out_file, argv[2]);
+        offset += 2;
+    }
+
+    if(strcmp(argv[1], "-h") == 0 || strcmp(argv[1], "--help") == 0)
+    {
+        usage(argv[0]);
+        return 0;
+    }
+
+    prog_name = (char *) calloc(strlen(argv[offset]), sizeof(char));
+    strcpy(prog_name, argv[offset]);
+    offset++;
+
+    if(offset < argc)
+        args = calloc(argc - offset, sizeof(char*));
+
+    for(int i = offset; i < argc; i++)
+        args[i - offset] = argv[i];
+
+    if((curpid = fork()) < 0)
+    {
+        perror("unable to fork()");
+        exit(1);
+    }
+
+    if(curpid == 0)
+    {
+        int fd_out = -1;
+        if(out_file)
+        {
+            /* Open the outfile with 664 permissions. */
+            fd_out = open(out_file,
+                          O_WRONLY | O_CREAT,
+                          S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH);
+        }
+        process_child(prog_name, args, fd_out);
+    }
+    else
+    {
+        struct rusage usage;
+        int who = RUSAGE_CHILDREN;
+        sleep(2);
+
+        waitpid(curpid, &status, 0);
+        
+        getrusage(who, &usage);
+
+        printf("user CPU time used:\t%lu %lu\n", usage.ru_utime.tv_sec, usage.ru_utime.tv_usec);
+        printf("system CPU time used:\t%lu %lu\n", usage.ru_stime.tv_sec, usage.ru_stime.tv_usec);
+        printf("residet set size used: %ld\n", usage.ru_maxrss);
+    }
+
+    return status;
+}