isodrive: first commit

src/configfsisomanager.cpp

@@ -0,0 +1,95 @@
+#include <iostream>
+#include <sys/stat.h>
+#include <sys/types.h>
+
+#include "util.h"
+#include "configfsisomanager.h"
+#include <dirent.h>
+#include <unistd.h>
+
+char *get_gadget_root()
+{
+	char *configFsRoot = fs_mount_point("configfs");
+	char *usbGadgetRoot = strjin(configFsRoot, "/usb_gadget/"); 
+	char *gadgetRoot = nullptr;
+
+	struct dirent *entry = nullptr;
+	DIR *dp = nullptr;
+	dp = opendir(usbGadgetRoot);
+	if (dp != nullptr)
+		while ((entry = readdir(dp)))
+		{
+			if (entry->d_name[0] != '.')
+			{
+				gadgetRoot = strjin(usbGadgetRoot, entry->d_name);
+				break;
+			}
+		}
+	return gadgetRoot;
+}
+
+char *get_config_root()
+{
+	char *gadgetRoot = get_gadget_root();
+	char *usbConfigRoot = strjin(gadgetRoot, "/configs/");
+	char *configRoot = nullptr;
+
+	struct dirent *entry = nullptr;
+	DIR *dp = nullptr;
+	dp = opendir(usbConfigRoot);
+	if (dp != nullptr)
+		while ((entry = readdir(dp)))
+		{
+			if (entry->d_name[0] != '.')
+			{
+				configRoot = strjin(usbConfigRoot, entry->d_name);
+				break;
+			}
+		}
+	return configRoot;
+}
+
+void mount_iso(char *iso_path)
+{
+	char *gadgetRoot = get_gadget_root();
+	char *configRoot = get_config_root();
+
+	char *functionRoot = strjin(gadgetRoot, "/functions");
+	char *massStorageRoot = strjin(functionRoot, "/mass_storage.0");
+	char *lunRoot = strjin(massStorageRoot, "/lun.0");
+	
+	char *stallFile = strjin(massStorageRoot, "stall");
+	char *udcFile = strjin(gadgetRoot, "/UDC");
+	char *lunFile = strjin(lunRoot, "/file");
+	char *lunCdRom = strjin(lunRoot, "/cdrom");
+	char *lunRo = strjin(lunRoot, "/ro");
+
+	reset_udc();
+	if (!isdir(massStorageRoot))
+	{
+		mkdir(massStorageRoot, S_IRWXU | S_IRWXG | S_IROTH | S_IXOTH);
+	}
+	if (!isdir(strjin(configRoot, "/mass_storage.0")))
+	{
+		symlink(massStorageRoot, strjin(configRoot, "/mass_storage.0"));
+	}
+	sysfs_write(lunFile, iso_path);
+	sysfs_write(lunCdRom, "1");
+	sysfs_write(lunRo, "1");
+
+	set_udc();
+}
+
+void reset_udc()
+{
+	char *gadget_root = get_gadget_root();
+	char *udcFile = strjin(gadget_root, "/UDC");
+	sysfs_write(udcFile, "");
+}
+
+void set_udc()
+{
+	char *gadget_root = get_gadget_root();
+	char *udcFile = strjin(gadget_root, "/UDC");
+	sysfs_write(udcFile, getprop("sys.usb.controller"));
+}

src/include/configfsisomanager.h

@@ -0,0 +1,11 @@
+#ifndef CONFIGFSISOMANAGER_H
+#define CONFIGFSISOMANAGER_H
+
+char *get_gadget_root();
+char *get_config_root();
+
+void mount_iso(char *iso_path);
+void set_udc();
+void reset_udc();
+
+#endif

src/include/util.h

@@ -0,0 +1,12 @@
+#ifndef UTIL_H
+#define UTIL_H
+
+char *fs_mount_point(char *filesystem_type);
+char *strjin(char *w1, char *w2);
+bool isdir(char *path);
+void sysfs_write(char *path, char *content);
+char *getprop(char *key);
+void trim(char *s);
+
+#endif
+

src/main.cpp

@@ -0,0 +1,24 @@
+#include "configfsisomanager.h"
+#include <iostream>
+#include <unistd.h>
+#include <stdio.h>
+
+int main(int argc, char* argv[]){
+	char *iso_target = argv[1];
+	if (getuid() != 0)
+	{
+		std::cerr << "Permission denied" << std::endl;
+		return 1;
+	}
+	if (argc == 1)
+	{
+		std::cerr << "Not enough args" << std::endl;
+		return 1;
+	}
+	if (iso_target[0] != '/')
+	{
+		std::cerr << "Iso path is not absolute" << std::endl;
+		return 1;
+	}
+	mount_iso(iso_target);
+}

src/util.cpp

@@ -0,0 +1,81 @@
+#include <fcntl.h>   
+#include <mntent.h>  
+#include <stdio.h>   
+#include <string.h>  
+#include <sys/stat.h>
+#include <unistd.h>
+#include <iostream>
+#include <fstream>
+#include <sstream>
+#include <array>
+#include <memory>
+
+
+// https://stackoverflow.com/a/123724
+void trim(char *s)
+{
+	char * p = s;
+	int l = strlen(p);
+	while(isspace(p[l - 1])) p[--l] = 0;
+	while(* p && isspace(* p)) ++p, --l;
+
+	memmove(s, p, l + 1);
+}
+
+char *fs_mount_point(char *filesystem_type) {
+	struct mntent *ent;
+	FILE *mounts;
+	char *mount_point = NULL;
+
+	mounts = setmntent("/proc/mounts", "r");
+	while (NULL != (ent = getmntent(mounts))) {
+		if (strcmp(ent->mnt_fsname, filesystem_type) == 0)
+		{
+			mount_point = ent->mnt_dir;
+			break;
+		}
+	}
+	return mount_point;
+}
+
+char *strjin(char *w1, char *w2)
+{
+	char *s = new char[strlen(w1)+strlen(w2)+1];
+	strcpy(s, w1);
+	strcat(s, w2);
+	return s;
+}
+
+bool isdir(char *path)
+{
+	struct stat sb;
+	if (stat(path, &sb) == 0)
+		return true;
+	else
+		return false;
+}
+
+void sysfs_write(char *path, char *content)
+{
+	std::cout << "Write: " << content << " -> " << path << std::endl;
+	int fd;
+	fd = open(path, O_WRONLY);
+	write(fd, content, 1);
+	close(fd);
+}
+
+char *getprop(char *key)
+{
+	std::array<char, 128> buffer;
+	char *value;
+	char *cmd = strjin("getprop ", key);
+	std::unique_ptr<FILE, decltype(&pclose)> pipe(popen(cmd, "r"), pclose);
+	while (fgets(buffer.data(), buffer.size(), pipe.get()) != nullptr)
+		value = strjin("", buffer.data());
+	trim(value);
+	return value;
+
+}
+
+
+