database: Copy the file pointer so we can keep the file open

[people/ms/libloc.git] / src / database.c

diff --git a/src/database.c b/src/database.c
index 85e3912fc0c4d37c4bec76992f342a97204485e6..9c07590f6cd3e10146e98848bfdc0375c51d8482 100644 (file)
--- a/src/database.c
+++ b/src/database.c
@@ -22,10 +22,13 @@
 #include <stdlib.h>
 #include <string.h>
 #include <sys/types.h>
 #include <stdlib.h>
 #include <string.h>
 #include <sys/types.h>

+#include <unistd.h>

 
 #include <loc/libloc.h>
 
 #include <loc/libloc.h>

+#include <loc/format.h>

 
 #include "libloc-private.h"
 
 #include "libloc-private.h"

+#include "as.h"

 #include "database.h"
 #include "stringpool.h"
 
 #include "database.h"
 #include "stringpool.h"
 


@@ -33,33 +36,16 @@ struct loc_database {
        struct loc_ctx* ctx;
        int refcount;
 
        struct loc_ctx* ctx;
        int refcount;
 

+       FILE* file;

        unsigned int version;
        off_t vendor;
        off_t description;
 
        unsigned int version;
        off_t vendor;
        off_t description;
 

-       struct loc_stringpool* pool;
-};
-
-const char* LOC_DATABASE_MAGIC = "LOCDBXX";
-unsigned int LOC_DATABASE_VERSION = 0;
-
-struct loc_database_magic {
-       char magic[7];
-
-       // Database version information
-       uint8_t version;
-};
-
-struct loc_database_header_v0 {
-       // Vendor who created the database
-       uint32_t vendor;
-
-       // Description of the database
-       uint32_t description;
+       // ASes in the database
+       struct loc_as** as;
+       size_t as_count;

 
 

-       // Tells us where the pool starts
-       uint32_t pool_offset;
-       uint32_t pool_length;
+       struct loc_stringpool* pool;

 };
 
 LOC_EXPORT int loc_database_new(struct loc_ctx* ctx, struct loc_database** database, size_t pool_size) {
 };
 
 LOC_EXPORT int loc_database_new(struct loc_ctx* ctx, struct loc_database** database, size_t pool_size) {


@@ -102,8 +88,20 @@ LOC_EXPORT struct loc_database* loc_database_ref(struct loc_database* db) {
 static void loc_database_free(struct loc_database* db) {
        DEBUG(db->ctx, "Releasing database %p\n", db);
 
 static void loc_database_free(struct loc_database* db) {
        DEBUG(db->ctx, "Releasing database %p\n", db);
 

+       // Remove references to all ASes
+       if (db->as) {
+               for (unsigned int i = 0; i < db->as_count; i++) {
+                       loc_as_unref(db->as[i]);
+               }
+               free(db->as);
+       }
+

        loc_stringpool_unref(db->pool);
 
        loc_stringpool_unref(db->pool);
 

+       // Close file
+       if (db->file)
+               fclose(db->file);
+

        loc_unref(db->ctx);
        free(db);
 }
        loc_unref(db->ctx);
        free(db);
 }


@@ -144,11 +142,67 @@ LOC_EXPORT int loc_database_set_description(struct loc_database* db, const char*
        return 0;
 }
 
        return 0;
 }
 

-static int loc_database_read_magic(struct loc_database* db, FILE* f) {
+LOC_EXPORT size_t loc_database_count_as(struct loc_database* db) {
+       return db->as_count;
+}
+
+static int loc_database_has_as(struct loc_database* db, struct loc_as* as) {
+       for (unsigned int i = 0; i < db->as_count; i++) {
+               if (loc_as_cmp(as, db->as[i]) == 0)
+                       return i;
+       }
+
+       return -1;
+}
+
+static int __loc_as_cmp(const void* as1, const void* as2) {
+       return loc_as_cmp(*(struct loc_as**)as1, *(struct loc_as**)as2);
+}
+
+static void loc_database_sort_ases(struct loc_database* db) {
+       qsort(db->as, db->as_count, sizeof(*db->as), __loc_as_cmp);
+}
+
+static struct loc_as* __loc_database_add_as(struct loc_database* db, struct loc_as* as) {
+       // Check if AS exists already
+       int i = loc_database_has_as(db, as);
+       if (i >= 0) {
+               loc_as_unref(as);
+
+               // Select already existing AS
+               as = db->as[i];
+
+               return loc_as_ref(as);
+       }
+
+       db->as_count++;
+
+       // Make space for the new entry
+       db->as = realloc(db->as, sizeof(*db->as) * db->as_count);
+
+       // Add the new entry at the end
+       db->as[db->as_count - 1] = loc_as_ref(as);
+
+       // Sort everything
+       loc_database_sort_ases(db);
+
+       return as;
+}
+
+LOC_EXPORT struct loc_as* loc_database_add_as(struct loc_database* db, uint32_t number) {
+       struct loc_as* as;
+       int r = loc_as_new(db->ctx, db->pool, &as, number);
+       if (r)
+               return NULL;
+
+       return __loc_database_add_as(db, as);
+}
+
+static int loc_database_read_magic(struct loc_database* db) {

        struct loc_database_magic magic;
 
        // Read from file
        struct loc_database_magic magic;
 
        // Read from file

-       size_t bytes_read = fread(&magic, 1, sizeof(magic), f);
+       size_t bytes_read = fread(&magic, 1, sizeof(magic), db->file);

 
        // Check if we have been able to read enough data
        if (bytes_read < sizeof(magic)) {
 
        // Check if we have been able to read enough data
        if (bytes_read < sizeof(magic)) {


@@ -174,11 +228,45 @@ static int loc_database_read_magic(struct loc_database* db, FILE* f) {
        return 1;
 }
 
        return 1;
 }
 

-static int loc_database_read_header_v0(struct loc_database* db, FILE* f) {
+static int loc_database_read_as_section_v0(struct loc_database* db,
+               off_t as_offset, size_t as_length) {
+       struct loc_database_as_v0 dbobj;
+
+       // Read from the start of the section
+       int r = fseek(db->file, as_offset, SEEK_SET);
+       if (r)
+               return r;
+
+       // Read all ASes
+       size_t as_count = as_length / sizeof(dbobj);
+       for (unsigned int i = 0; i < as_count; i++) {
+               size_t bytes_read = fread(&dbobj, 1, sizeof(dbobj), db->file);
+               if (bytes_read < sizeof(dbobj)) {
+                       ERROR(db->ctx, "Could not read an AS object\n");
+                       return -ENOMSG;
+               }
+
+               // Allocate a new AS
+               struct loc_as* as;
+               r = loc_as_new_from_database_v0(db->ctx, db->pool, &as, &dbobj);
+               if (r)
+                       return r;
+
+               // Attach it to the database
+               as = __loc_database_add_as(db, as);
+               loc_as_unref(as);
+       }
+
+       INFO(db->ctx, "Read %zu ASes from the database\n", db->as_count);
+
+       return 0;
+}
+
+static int loc_database_read_header_v0(struct loc_database* db) {

        struct loc_database_header_v0 header;
 
        // Read from file
        struct loc_database_header_v0 header;
 
        // Read from file

-       size_t size = fread(&header, 1, sizeof(header), f);
+       size_t size = fread(&header, 1, sizeof(header), db->file);

 
        if (size < sizeof(header)) {
                ERROR(db->ctx, "Could not read enough data for header\n");
 
        if (size < sizeof(header)) {
                ERROR(db->ctx, "Could not read enough data for header\n");


@@ -193,17 +281,25 @@ static int loc_database_read_header_v0(struct loc_database* db, FILE* f) {
        off_t pool_offset  = ntohl(header.pool_offset);
        size_t pool_length = ntohl(header.pool_length);
 
        off_t pool_offset  = ntohl(header.pool_offset);
        size_t pool_length = ntohl(header.pool_length);
 

-       int r = loc_stringpool_read(db->pool, f, pool_offset, pool_length);
+       int r = loc_stringpool_read(db->pool, db->file, pool_offset, pool_length);
+       if (r)
+               return r;
+
+       // AS section
+       off_t as_offset  = ntohl(header.as_offset);
+       size_t as_length = ntohl(header.as_length);
+
+       r = loc_database_read_as_section_v0(db, as_offset, as_length);

        if (r)
                return r;
 
        return 0;
 }
 
        if (r)
                return r;
 
        return 0;
 }
 

-static int loc_database_read_header(struct loc_database* db, FILE* f) {
+static int loc_database_read_header(struct loc_database* db) {

        switch (db->version) {
                case 0:
        switch (db->version) {
                case 0:

-                       return loc_database_read_header_v0(db, f);
+                       return loc_database_read_header_v0(db);

 
                default:
                        ERROR(db->ctx, "Incompatible database version: %u\n", db->version);
 
                default:
                        ERROR(db->ctx, "Incompatible database version: %u\n", db->version);


@@ -212,17 +308,29 @@ static int loc_database_read_header(struct loc_database* db, FILE* f) {
 }
 
 LOC_EXPORT int loc_database_read(struct loc_database* db, FILE* f) {
 }
 
 LOC_EXPORT int loc_database_read(struct loc_database* db, FILE* f) {

-       int r = fseek(f, 0, SEEK_SET);
+       // Copy the file pointer and work on that so we don't care if
+       // the calling function closes the file
+       int fd = fileno(f);
+
+       // Make a copy
+       fd = dup(fd);
+
+       // Retrieve a file pointer
+       db->file = fdopen(fd, "r");
+       if (!db->file)
+               return -errno;
+
+       int r = fseek(db->file, 0, SEEK_SET);

        if (r)
                return r;
 
        // Read magic bytes
        if (r)
                return r;
 
        // Read magic bytes

-       r = loc_database_read_magic(db, f);
+       r = loc_database_read_magic(db);

        if (r)
                return r;
 
        // Read the header
        if (r)
                return r;
 
        // Read the header

-       r = loc_database_read_header(db, f);
+       r = loc_database_read_header(db);

        if (r)
                return r;
 
        if (r)
                return r;
 


@@ -266,6 +374,19 @@ LOC_EXPORT int loc_database_write(struct loc_database* db, FILE* f) {
        }
        offset += sizeof(header);
 
        }
        offset += sizeof(header);
 

+       // Write all ASes
+       header.as_offset = htonl(offset);
+
+       struct loc_database_as_v0 dbas;
+       for (unsigned int i = 0; i < db->as_count; i++) {
+               // Convert AS into database format
+               loc_as_to_database_v0(db->as[i], &dbas);
+
+               // Write to disk
+               offset += fwrite(&dbas, 1, sizeof(dbas), f);
+       }
+       header.as_length = htonl(db->as_count * sizeof(dbas));
+

        // Save the offset of the pool section
        DEBUG(db->ctx, "Pool starts at %jd bytes\n", offset);
        header.pool_offset = htonl(offset);
        // Save the offset of the pool section
        DEBUG(db->ctx, "Pool starts at %jd bytes\n", offset);
        header.pool_offset = htonl(offset);