[6model/c] add hashtable and a few tests (works only on Linux)

c/Configure.bat

@@ -1,6 +1,7 @@
 :: Configure.bat
 
-:: This script is written for Microsoft Visual C++ Express 2010 or GCC.
+:: This script should work on a Microsoft Windows operating system with
+:: either Microsoft Visual C++ or GNU Compiler Collection gcc.
 
 :: TODO
 :: - Add a --help option and provide for more options in general
@@ -65,4 +66,4 @@ tools\build\Configure.exe tools\build\Makefile.in Makefile
 :: friendliness grounds, .bat reassures the reader that the script will do
 :: only "simple" things.
 :: You could argue it the other way - we use cmd.exe, not command.com, so we
-:: should use the extension that command.com cannot handle.  Dunno...
+:: should use the extension that command.com cannot handle.  Dunno...

c/Configure.sh

@@ -1,5 +1,7 @@
 #!/bin/sh
 # TODO
 # - Add a --help option and provide for more options in general
-cc -Wall -o tools/build/Configure tools/build/Configure.c
-tools/build/Configure tools/build/Makefile.in Makefile
+export COMPILER=GCC
+set opts_gcc=-Wall -DCC=$COMPILER
+cc $opts_gcc -o tools/build/Configure tools/build/Configure.c
+tools/build/Configure tools/build/Makefile.in Makefile

c/src/hashtable.h

@@ -0,0 +1,74 @@
+/* hashtable.h */
+
+/* Structures */
+
+/* hashtable_entry */
+struct hashtable_entry {
+    /* A hash entry is a key-value pair.  The key and the value can */
+    /* each be an arbitrary array of bytes. */
+    /* This is a frequently accessed data structure.  For address */
+    /* alignment and efficient memory access all the pointers are */
+    /* defined at the beginning and the other members ordered by */
+    /* decreasing size and frquency of use after that.  Some C */
+    /* compilers may do that anyway, but maintaining the order in the */
+    /* source code is only a small effort. */
+    void * keypointer;
+    void * valuepointer;
+    int    keyint;
+    int    valueint;
+    /* A hash entry can also be empty, for example after a delete. */
+    /* The empty entries are arranged in a linked list ordered by */
+    /* position in the hash entry table, so that subsequent re-use */
+    /* occurs in the entry nearest the start of the table.  The empty */
+    /* entry list is doubly linked so that the average addition needs */
+    /* to walk only a quarter of the list (single linked would have */
+    /* needed to walk half the list on average). */
+    /* In an empty entry, keypointer == NULL, keyint == 0, */
+    /* (int)valuepointer == forward link subscript (-1 ends), */
+    /* valueint == backward link subscript (-1 ends). */
+};
+
+/* hashtable_bucket */
+struct hashtable_bucket {
+    int * list; /* list of indices into hash entry list */
+    int   size;
+};
+
+/* hashtable */
+struct hashtable {
+    /* This is a frequently accessed data structure.  For best memory */
+    /* alignment, all the pointer fields are at the beginning and the */
+    /* other members ordered by decreasing size and popularity after */
+    /* that.  Some compilers may do that anyway, but manual ordering */
+    /* is only a slight inconvenience. */
+    struct hashtable_entry  * entrylist;
+    struct hashtable_bucket * bucketlist1;
+    struct hashtable_bucket * bucketlist2;
+    float loadfactorlow;  /* threshold to halve the number of buckets */
+    float loadfactorhigh; /* threshold to double number of buckets */
+    int salt;             /* random seed for hashing function */
+    int entrylistsize;    /* total including deleted entries */
+    int entrycount;       /* number of actual (not deleted) entries */
+    int deletedentryhead; /* head of linked list of deleted entries */
+    int deletedentrytail; /* tail of linked list of deleted entries */
+    int bucketmask1;      /* eg 0x3f when there are 64 buckets */
+    int bucketmask2;      /* eg 0x3f when there are 64 buckets */
+    int emptybuckets;     /* to decide when to shorten bucket list */
+};
+
+/* hashtable_iterator */
+struct hashtable_iterator {
+    struct hashtable * hashtable;
+    int    nextentryindex;  /* >=0 when iterating, -1 when done */
+};
+
+/* Function declarations */
+struct hashtable * hashtable_new();
+int  hashtable_store(struct hashtable * hash, void * keypointer, int keylength, void * valuepointer, int valueint);
+int  hashtable_fetch(struct hashtable * hash, void * keypointer, int keylength, void ** valuepointerpointer, int * valueintpointer);
+int  hashtable_delete(struct hashtable * hash, void * keypointer, int keylength);
+void hashtable_free(struct hashtable * hash);
+void hashtable_iterator_init(struct hashtable * hash, struct hashtable_iterator * iter);
+int  hashtable_iterator_next(struct hashtable_iterator * iter, struct hashtable_entry * entry);
+
+/* end of hashtable.h */

c/t/01-toolchain/01a-cc.c

@@ -137,13 +137,13 @@ remove_exe()
         perror("01a-cc error 6:");
         exit(6);
     }
-    printf("ok 6 - unlink testexe.c\n");
+    printf("ok 6 - remove testexe.c\n");
     status = unlink("testexe" EXT_EXE);
     if (status) {
         perror("01a-cc error 7:");
         exit(5);
     }
-    printf("ok 7 - unlink testexe" EXT_EXE "\n");
+    printf("ok 7 - remove testexe" EXT_EXE "\n");
 }
 
 
@@ -173,7 +173,7 @@ create_lib()
     );
     fclose(testlib_sourcefile);
     #ifdef _WIN32
-        #ifdef MSVC
+        #ifdef _MSC_VER
             status = system("cl -LD -WX -nologo testlib.c >nul"); /* Visual C++ */
         #else
             status = system("gcc -mdll -o testlib.dll testlib.c"); /* MinGW */
@@ -183,6 +183,9 @@ create_lib()
         if (status==0) {
             status = system("cc -shared -s -o testlib.so testlib.o");
         }
+        if (status==0) {
+            status = system("rm testlib.o");
+        }
     #endif
     if (status) {
         perror("01a-cc error 8:");
@@ -215,38 +218,38 @@ load_lib()
             exit(9);
         }
     #endif
-    printf("ok 9 - loaded testlib" EXT_DYNLIB "\n");
+    printf("ok 9 - load testlib" EXT_DYNLIB "\n");
 
     #ifdef _WIN32
         pfunction = GetProcAddress(testlib, "testfunction");
     #else
         dlerror(); /* clear any possible error */
         pfunction = dlsym(testlib, "testfunction");
         if( (error = dlerror()) != NULL ) {
-            fprintf(stderr, "01a-cc error 11: %s\n", error);
+            fprintf(stderr, "01a-cc error 10: %s\n", error);
             exit(10);
         }
     #endif
     if (pfunction == NULL) {
-        fprintf(stderr, "01a-cc error 11a: GetProcAddress returned NULL\n");
-        exit(11);
+        fprintf(stderr, "01a-cc error 10a: GetProcAddress returned NULL\n");
+        exit(10);
     }
-    printf("ok 11 - dlsym testfunction\n");
-    result = (* pfunction)(12, "call testfunction"); /* prints "ok 12" */
-    if (result == 42+12)
-        printf("ok 13 - testfunction result\n");
+    printf("ok 10 - dlsym testfunction\n");
+    result = (* pfunction)(11, "call testfunction"); /* prints "ok 12" */
+    if (result == 42+11)
+        printf("ok 12 - testfunction result\n");
     else
-        printf("not ok 13 - testfunction result\n");
+        printf("not ok 12 - testfunction result\n");
     #ifdef _WIN32
         result = ! FreeLibrary(testlib); /* returns 0 for failure! */
     #else
         result = dlclose(testlib);
     #endif
     if (result) {
-        fprintf(stderr, "01a-cc error 14: %s\n", error);
+        fprintf(stderr, "01a-cc error 13: %s\n", error);
         exit(EXIT_FAILURE);
     }
-    printf("ok 14 - dlclose\n");
+    printf("ok 13 - unload library\n");
 }
 
 
@@ -257,34 +260,34 @@ remove_lib()
     int status;
     status = unlink("testlib.c");
     if (status) {
-        perror("01a-cc error 15:");
-        exit(15);
+        perror("01a-cc error 14:");
+        exit(14);
     }
-    printf("ok 15 - unlink testlib.c\n");
-    #ifdef MSVC
+    printf("ok 14 - remove testlib.c\n");
+    #ifdef _MSC_VER
         status = unlink("testlib" EXT_OBJ);
         if (status) {
-            perror("01a-cc error 16:");
-            exit(16);
+            perror("01a-cc error 15:");
+            exit(15);
         }
-        printf("ok 16 - unlink testlib" EXT_OBJ "\n");
+        printf("ok 15 - remove testlib" EXT_OBJ "\n");
     #else
-        printf("ok 16 - unlink testlib # SKIPPED\n");
+        printf("ok 15 - remove testlib # SKIPPED\n"); /* MinGW */
     #endif
     status = unlink("testlib" EXT_DYNLIB);
     if (status) {
-        perror("01a-cc error 17:");
-        exit(17);
+        perror("01a-cc error 16:");
+        exit(16);
     }
-    printf("ok 17 - unlink testlib" EXT_DYNLIB "\n");
+    printf("ok 16 - remove testlib" EXT_DYNLIB "\n");
 }
 
 
 /* main */
 int
 main(int argc, char * argv[])
 {
-    printf("1..17\n"); /* tests */
+    printf("1..16\n"); /* tests */
     create_exe();  /* 1-2 make testexe.c and testexe.exe */
     run_exe();     /* 2-5 run testexe.exe */
     remove_exe();  /* 6-7 remove testexe.c and testexe.exe */