Complete procfs

kernel/include/vfs/file.hpp

@@ -27,6 +27,10 @@ struct file {
     //File system specific
     size_t location;
     size_t position;
+
+    file(){};
+    file(std::string file_name, bool directory, bool hidden, bool system, uint64_t size)
+        : file_name(file_name), directory(directory), hidden(hidden), system(system), size(size) {};
 };
 
 } //end of namespace vfs

kernel/src/fs/procfs.cpp

@@ -13,11 +13,63 @@
 #include "fs/procfs.hpp"
 
 #include "scheduler.hpp"
+#include "logging.hpp"
 
 namespace {
 
 const scheduler::process_control_t* pcb = nullptr;
 
+std::vector<vfs::file> standard_contents;
+
+//TODO Move into tstl
+uint64_t atoui(const std::string& s){
+    uint64_t value = 0;
+    uint64_t mul = 1;
+
+    for(size_t i = s.size(); i > 0; --i){
+        auto c = s[i - 1];
+
+        if(c < '0' || c  > '9'){
+            return value;
+        }
+
+        value += mul * (c - '0');
+
+        mul *= 10;
+    }
+
+    return value;
+}
+
+size_t read(const std::string& value, char* buffer, size_t count, size_t offset, size_t& read){
+    if(offset > value.size()){
+        return std::ERROR_INVALID_OFFSET;
+    }
+
+    read = std::min(count, value.size() - offset);
+    std::copy_n(buffer, value.c_str() + offset, read);
+
+    return 0;
+}
+
+std::string get_value(uint64_t pid, const std::string& name){
+    auto& process = pcb[pid];
+
+    if(name == "pid"){
+        return std::to_string(process.process.pid);
+    } else if(name == "ppid"){
+        return std::to_string(process.process.ppid);
+    } else if(name == "state"){
+        return std::to_string(static_cast<uint8_t>(process.state));
+    } else if(name == "system"){
+        return process.process.system ? "true" : "false";
+    } else if(name == "priority"){
+        return std::to_string(process.process.priority);
+    } else {
+        return "";
+    }
+}
+
 } //end of anonymous namespace
 
 void procfs::set_pcb(const scheduler::process_control_t* pcb_ptr){
@@ -25,7 +77,11 @@ void procfs::set_pcb(const scheduler::process_control_t* pcb_ptr){
 }
 
 procfs::procfs_file_system::procfs_file_system(std::string mp) : mount_point(mp) {
-    //Nothing to init
+    standard_contents.emplace_back("pid", false, false, false, 0);
+    standard_contents.emplace_back("ppid", false, false, false, 0);
+    standard_contents.emplace_back("state", false, false, false, 0);
+    standard_contents.emplace_back("system", false, false, false, 0);
+    standard_contents.emplace_back("priority", false, false, false, 0);
 }
 
 procfs::procfs_file_system::~procfs_file_system(){
@@ -33,6 +89,7 @@ procfs::procfs_file_system::~procfs_file_system(){
 }
 
 size_t procfs::procfs_file_system::get_file(const std::vector<std::string>& file_path, vfs::file& f){
+    // Access the root folder
     if(file_path.empty()){
         f.file_name = "/";
         f.directory = true;
@@ -43,23 +100,85 @@ size_t procfs::procfs_file_system::get_file(const std::vector<std::string>& file
         return 0;
     }
 
-    if(file_path.size() == 1){
-        //TODO
+    auto i = atoui(file_path[0]);
+
+    // Check the pid folder
+    if(i >= scheduler::MAX_PROCESS){
+        return std::ERROR_NOT_EXISTS;
     }
 
+    auto& process = pcb[i];
+
+    if(process.state == scheduler::process_state::EMPTY){
+        return std::ERROR_NOT_EXISTS;
+    }
+
+    // Access a pid folder
+    if(file_path.size() == 1){
+        f.file_name = file_path[0];
+        f.directory = true;
+        f.hidden = false;
+        f.system = false;
+        f.size = 0;
+
+        return 0;
+    }
+
+    // Access a file directly
+    if(file_path.size() == 2){
+        auto value = get_value(i, file_path[1]);
+
+        if(value.size()){
+            f.file_name = file_path[1];
+            f.directory = false;
+            f.hidden = false;
+            f.system = false;
+            f.size = value.size();
+
+            return 0;
+        } else {
+            return std::ERROR_NOT_EXISTS;
+        }
+    }
+
+    // There are no more levels
     return std::ERROR_NOT_EXISTS;
 }
 
 size_t procfs::procfs_file_system::read(const std::vector<std::string>& file_path, char* buffer, size_t count, size_t offset, size_t& read){
-    //Cannot access the root for reading
+    //Cannot access the root nor the pid directores for reading
     if(file_path.size() < 2){
         return std::ERROR_PERMISSION_DENIED;
     }
 
+    if(file_path.size() == 2){
+        auto i = atoui(file_path[0]);
+
+        if(i >= scheduler::MAX_PROCESS){
+            return std::ERROR_NOT_EXISTS;
+        }
+
+        auto& process = pcb[i];
+
+        if(process.state == scheduler::process_state::EMPTY){
+            return std::ERROR_NOT_EXISTS;
+        }
+
+        auto value = get_value(i, file_path[1]);
+
+        if(value.size()){
+            return ::read(value, buffer, count, offset, read);
+        } else {
+            return std::ERROR_NOT_EXISTS;
+        }
+    }
+
     return std::ERROR_NOT_EXISTS;
 }
 
 size_t procfs::procfs_file_system::ls(const std::vector<std::string>& file_path, std::vector<vfs::file>& contents){
+    logging::logf(logging::log_level::DEBUG, "procfs ls %u\n", file_path.size());
+
     if(file_path.size() == 0){
         for(size_t i = 0; i < scheduler::MAX_PROCESS; ++i){
             auto& process = pcb[i];
@@ -67,23 +186,26 @@ size_t procfs::procfs_file_system::ls(const std::vector<std::string>& file_path,
             if(process.state != scheduler::process_state::EMPTY){
                 vfs::file f;
                 f.file_name = std::to_string(process.process.pid);
-                f.directory = false;
+                f.directory = true;
                 f.hidden = false;
                 f.system = false;
                 f.size = 0;
                 contents.emplace_back(std::move(f));
             }
         }
-    }
-
-    //No subfolder support
-    if(file_path.size() > 0){
-        return std::ERROR_NOT_EXISTS;
-    }
 
         return 0;
     }
 
+    if(file_path.size() == 1){
+        contents = standard_contents;
+        return 0;
+    }
+
+    //No more subfolder support
+    return std::ERROR_NOT_EXISTS;
+}
+
 size_t procfs::procfs_file_system::statfs(statfs_info& file){
     file.total_size = 0;
     file.free_size = 0;