zynaddsubfx

commit b7823300567216d65314b86f42130b1d37694fe2
parent de95680bcef1f009f4f1ea5154a1c4d056c9eefb
Author: fundamental <mark.d.mccurry@gmail.com>
Date:   Wed, 17 Aug 2016 21:47:13 -0400

Add Bank Cache To Speed Up Startup With Slow IO

Diffstat:
M
src/Misc/BankDb.cpp
 | 
102
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++----
M
src/Misc/BankDb.h
 | 
10
+++++++---

2 files changed, 104 insertions(+), 8 deletions(-)
diff --git a/src/Misc/BankDb.cpp b/src/Misc/BankDb.cpp
@@ -1,8 +1,10 @@
 #include "BankDb.h"
 #include "XMLwrapper.h"
+#include "Util.h"
 #include "../globals.h"
 #include <cstring>
 #include <dirent.h>
+#include <sys/stat.h>
 
 #define INSTRUMENT_EXTENSION ".xiz"
 
@@ -11,7 +13,7 @@ typedef BankDb::svec svec;
 typedef BankDb::bvec bvec;
 
 BankEntry::BankEntry(void)
-    :id(0), add(false), pad(false), sub(false)
+    :id(0), add(false), pad(false), sub(false), time(0)
 {}
 
 bool platform_strcasestr(const char *hay, const char *needle)
@@ -114,9 +116,77 @@ void BankDb::clear(void)
     fields.clear();
 }
 
+static std::string getCacheName(void)
+{
+    char name[512] = {0};
+    snprintf(name, sizeof(name), "%s%s", getenv("HOME"),
+            "/.zynaddsubfx-bank-cache.xml");
+    return name;
+}
+
+static bvec loadCache(void)
+{
+    bvec cache;
+    XMLwrapper xml;
+    xml.loadXMLfile(getCacheName());
+    if(xml.enterbranch("bank-cache")) {
+        auto nodes = xml.getBranch();
+
+        for(auto node:nodes) {
+            BankEntry be;
+#define bind(x,y) if(node.has(#x)) {be.x = y(node[#x].c_str());}
+            bind(file, string);
+            bind(bank, string);
+            bind(name, string);
+            bind(comments, string);
+            bind(author, string);
+            bind(type, atoi);
+            bind(id, atoi);
+            bind(add, atoi);
+            bind(pad, atoi);
+            bind(sub, atoi);
+            bind(time, atoi);
+#undef bind
+            cache.push_back(be);
+        }
+    }
+    return cache;
+}
+
+static void saveCache(bvec vec)
+{
+    XMLwrapper xml;
+    xml.beginbranch("bank-cache");
+    for(auto value:vec) {
+        XmlNode binding("instrument-entry");
+#define bind(x) binding[#x] = to_s(value.x);
+        bind(file);
+        bind(bank);
+        bind(name);
+        bind(comments);
+        bind(author);
+        bind(type);
+        bind(id);
+        bind(add);
+        bind(pad);
+        bind(sub);
+        bind(time);
+#undef bind
+        xml.add(binding);
+    }
+    xml.endbranch();
+    xml.saveXMLfile(getCacheName(), 0);
+}
+
 void BankDb::scanBanks(void)
 {
     fields.clear();
+    bvec cache = loadCache();
+    bmap cc;
+    for(auto c:cache)
+        cc[c.bank + c.file] = c;
+
+    bvec ncache;
     for(auto bank:banks)
     {
         DIR *dir = opendir(bank.c_str());
@@ -124,6 +194,7 @@ void BankDb::scanBanks(void)
         if(!dir)
             continue;
 
+
         struct dirent *fn;
 
         while((fn = readdir(dir))) {
@@ -133,16 +204,36 @@ void BankDb::scanBanks(void)
             if(!strstr(filename, INSTRUMENT_EXTENSION))
                 continue;
 
-            auto xiz = processXiz(filename, bank);
+            auto xiz = processXiz(filename, bank, cc);
             fields.push_back(xiz);
+            ncache.push_back(xiz);
         }
 
         closedir(dir);
+
     }
+    saveCache(ncache);
 }
 
-BankEntry BankDb::processXiz(std::string filename, std::string bank) const
+BankEntry BankDb::processXiz(std::string filename,
+        std::string bank, bmap &cache) const
 {
+    string fname = bank+filename;
+
+    //Grab a timestamp
+    struct stat st;
+    int ret  = lstat(fname.c_str(), &st);
+    int time = 0;
+    if(ret != -1)
+        time = st.st_mtim.tv_sec;
+
+    //quickly check if the file exists in the cache and if it is up-to-date
+    if(cache.find(fname) != cache.end() &&
+            cache[fname].time == time)
+        return cache[fname];
+
+
+
     //verify if the name is like this NNNN-name (where N is a digit)
     int no = 0;
     unsigned int startname = 0;
@@ -175,6 +266,7 @@ BankEntry BankDb::processXiz(std::string filename, std::string bank) const
     entry.file = filename;
     entry.bank = bank;
     entry.id   = no;
+    entry.time = time;
 
     if(no != 0) //the instrument position in the bank is found
         entry.name = name.substr(startname);
@@ -201,10 +293,10 @@ BankEntry BankDb::processXiz(std::string filename, std::string bank) const
         "Sound Effects",
     };
 
+
     //Try to obtain other metadata (expensive)
     XMLwrapper xml;
-    string fname = bank+filename;
-    int ret = xml.loadXMLfile(fname);
+    ret = xml.loadXMLfile(fname);
     if(xml.enterbranch("INSTRUMENT")) {
         if(xml.enterbranch("INFO")) {
             char author[1024];
diff --git a/src/Misc/BankDb.h b/src/Misc/BankDb.h
@@ -1,6 +1,7 @@
 #pragma once
 #include <string>
 #include <vector>
+#include <map>
 
 struct BankEntry
 {
@@ -15,16 +16,19 @@ struct BankEntry
     bool        add;
     bool        pad;
     bool        sub;
+    int         time;//last update
     typedef std::vector<std::string> svec;
     svec tags(void) const;
     bool match(std::string) const;
 };
 
+
 class BankDb
 {
     public:
-        typedef std::vector<std::string> svec;
-        typedef std::vector<BankEntry>   bvec;
+        typedef std::vector<std::string>        svec;
+        typedef std::vector<BankEntry>          bvec;
+        typedef std::map<std::string,BankEntry> bmap;
 
         //search for banks
         //uses a space separated list of keywords and
@@ -44,7 +48,7 @@ class BankDb
         void scanBanks(void);
 
     private:
-        BankEntry processXiz(std::string, std::string) const;
+        BankEntry processXiz(std::string, std::string, bmap&) const;
         bvec fields;
         svec banks;
 };