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+                    GNU GENERAL PUBLIC LICENSE
+                       Version 3, 29 June 2007
+
+ Copyright (C) 2007 Free Software Foundation, Inc. <https://fsf.org/>
+ Everyone is permitted to copy and distribute verbatim copies
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+
+                            Preamble
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+ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
+
+  16. Limitation of Liability.
+
+  IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
+WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS
+THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY
+GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
+USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
+DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
+PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
+EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
+SUCH DAMAGES.
+
+  17. Interpretation of Sections 15 and 16.
+
+  If the disclaimer of warranty and limitation of liability provided
+above cannot be given local legal effect according to their terms,
+reviewing courts shall apply local law that most closely approximates
+an absolute waiver of all civil liability in connection with the
+Program, unless a warranty or assumption of liability accompanies a
+copy of the Program in return for a fee.
+
+                     END OF TERMS AND CONDITIONS
+
+            How to Apply These Terms to Your New Programs
+
+  If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+  To do so, attach the following notices to the program.  It is safest
+to attach them to the start of each source file to most effectively
+state the exclusion of warranty; and each file should have at least
+the "copyright" line and a pointer to where the full notice is found.
+
+    <one line to give the program's name and a brief idea of what it does.>
+    Copyright (C) <year>  <name of author>
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+Also add information on how to contact you by electronic and paper mail.
+
+  If the program does terminal interaction, make it output a short
+notice like this when it starts in an interactive mode:
+
+    <program>  Copyright (C) <year>  <name of author>
+    This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
+    This is free software, and you are welcome to redistribute it
+    under certain conditions; type `show c' for details.
+
+The hypothetical commands `show w' and `show c' should show the appropriate
+parts of the General Public License.  Of course, your program's commands
+might be different; for a GUI interface, you would use an "about box".
+
+  You should also get your employer (if you work as a programmer) or school,
+if any, to sign a "copyright disclaimer" for the program, if necessary.
+For more information on this, and how to apply and follow the GNU GPL, see
+<https://www.gnu.org/licenses/>.
+
+  The GNU General Public License does not permit incorporating your program
+into proprietary programs.  If your program is a subroutine library, you
+may consider it more useful to permit linking proprietary applications with
+the library.  If this is what you want to do, use the GNU Lesser General
+Public License instead of this License.  But first, please read
+<https://www.gnu.org/licenses/why-not-lgpl.html>.
+
diff --git a/libgs/Makefile b/libgs/Makefile
new file mode 100644
index 0000000..8714519
--- /dev/null
+++ b/libgs/Makefile
@@ -0,0 +1,48 @@
+.POSIX:
+CC=cc
+CFLAGS=-pedantic -o2 -pipe -Wall -Wextra -Wno-unused-parameter -fPIC -shared
+LDFLAGS=-lcurl -ljansson
+TARGET=libgs.so
+
+OBJECTS=src/gs.o \
+	src/app.o \
+	src/account.o \
+	src/auth.o \
+	src/client.o \
+	src/http.o \
+	src/log.o \
+	src/timeline.o \
+	src/status.o \
+	src/string-util.o
+
+all: $(TARGET)
+
+$(TARGET): $(OBJECTS)
+	$(CC) $(CFLAGS) -o $@ $(OBJECTS) $(LDFLAGS)
+
+.c.o:
+	$(CC) $(CFLAGS) -c -o $@ $<
+
+clean: 
+	rm -f src/*.o
+	rm -f $(TARGET)
+
+src/account.o: src/account.c src/account.h src/log.h
+src/app.o: src/app.c src/app.h src/http.h src/log.h
+src/auth.o: src/auth.c src/auth.h src/client.h src/log.h \
+	src/string-util.h
+src/client.o: src/client.c src/client.h src/http.h src/log.h \
+ src/string-util.h
+src/config.o: src/config.c src/string-util.h src/config.h src/log.h
+src/gs.o: src/gs.c src/gs.h src/app.h src/account.h src/auth.h \
+	src/client.h src/http.h src/log.h src/string-util.h src/status.h \
+	src/timeline.h
+src/http.o: src/http.c src/string-util.h src/auth.h src/client.h \
+	src/log.h
+src/instance_info.o: src/instance_info.c src/instance_info.h src/log.h
+src/log.o: src/log.c src/log.h
+src/status.o: src/status.c src/status.h src/account.h src/log.h
+src/string-util.o: src/string-util.c
+src/timeline.o: src/timeline.c src/timeline.h src/status.h src/account.h \
+	src/client.h src/auth.h src/config.h src/http.h src/string-util.h \
+	src/log.h
diff --git a/libgs/src/account.c b/libgs/src/account.c
new file mode 100644
index 0000000..ecf3c28
--- /dev/null
+++ b/libgs/src/account.c
@@ -0,0 +1,93 @@
+#define _POSIX_C_SOURCE 200809L
+#include <err.h>
+#include <string.h>
+#include <jansson.h>
+#include "account.h"
+#include "log.h"
+
+struct gs_account *gs_account_from_json(const char *json_data)
+{
+    struct gs_account *a;
+    json_t *root;
+    json_error_t error;
+
+    root = json_loads(json_data, 0, &error);
+    if (!root) {
+        gs_log(GS_WARNING, "gs_account_from_json", 
+                "json parse error: line %d: %s", error.line, error.text);
+        return NULL;
+    }
+
+    a = gs_account_from_json_t(root);
+    json_decref(root);
+    return a;
+}
+
+struct gs_account *gs_account_from_json_t(const json_t *root)
+{
+    struct gs_account *a;
+    if (!root) {
+        gs_log(GS_WARNING, "gs_account_from_json_t", "json data is null");
+        return NULL;
+    }
+
+    if (!json_is_object(root)) {
+        gs_log(GS_WARNING, "gs_account_from_json_t", 
+                "json root is not object");
+        return NULL;
+    }
+
+    a = calloc(1, sizeof(struct gs_account));
+    if (!a) {
+        err(1, "gs_account_from_json_t");
+        return NULL;
+    }
+
+    json_t *id = json_object_get(root, "id");
+    if (json_is_string(id)) {
+        a->id = strdup(json_string_value(id));
+    }
+
+    json_t *username = json_object_get(root, "username");
+    if (json_is_string(username)) {
+        a->username = strdup(json_string_value(username));
+    }
+
+    json_t *acct = json_object_get(root, "acct");
+    if (json_is_string(acct)) {
+        a->acct = strdup(json_string_value(acct));
+    }
+
+    json_t *display_name = json_object_get(root, "display_name");
+    if (json_is_string(display_name)) {
+        a->display_name = strdup(json_string_value(display_name));
+    }
+
+    return a;
+}
+
+void gs_account_free(struct gs_account *a)
+{
+    if (a->id)
+        free(a->id);
+    if (a->username)
+        free(a->username);
+    if (a->acct)
+        free(a->acct);
+    if (a->display_name)
+        free(a->display_name);
+    if (a->note)
+        free(a->note);
+    if (a->url)
+        free(a->url);
+    if (a->avatar)
+        free(a->avatar);
+    if (a->avatar_static)
+        free(a->avatar_static);
+    if (a->header)
+        free(a->header);
+    if (a->header_static)
+        free(a->header_static);
+    free(a);
+}
+
diff --git a/libgs/src/account.h b/libgs/src/account.h
new file mode 100644
index 0000000..c9d36d2
--- /dev/null
+++ b/libgs/src/account.h
@@ -0,0 +1,30 @@
+#ifndef __GS_ACCOUNT_H
+#define __GS_ACCOUNT_H
+
+#include <stdbool.h>
+#include <jansson.h>
+
+struct gs_account {
+    char *id;
+    char *username;
+    char *acct;
+    char *display_name;
+    bool locked;
+    unsigned int follower_count;
+    unsigned int following_count;
+    unsigned int statuses_count;
+    char *note;
+    char *url;
+    char *avatar;
+    char *avatar_static;
+    char *header;
+    char *header_static;
+    struct gs_account *moved;
+    bool bot;
+};
+
+struct gs_account *gs_account_from_json(const char *json_data);
+struct gs_account *gs_account_from_json_t(const json_t *);
+void gs_account_free(struct gs_account *);
+
+#endif
diff --git a/libgs/src/app.c b/libgs/src/app.c
new file mode 100644
index 0000000..b3f6e20
--- /dev/null
+++ b/libgs/src/app.c
@@ -0,0 +1,115 @@
+#define _POSIX_C_SOURCE 200809L
+#include <err.h>
+#include <jansson.h>
+#include <string.h>
+#include "app.h"
+#include "http.h"
+#include "log.h"
+
+#define CLIENT_NAME "ap_client"
+#define REGISTER_URL "https://%s/api/v1/apps"
+
+static char *get_register_url(const char *domain)
+{
+    char *url;
+    size_t size;
+
+    size = strlen(REGISTER_URL) + strlen(domain) - 1;
+    url = malloc(size);
+    if (!url) {
+        err(1, NULL);
+        return NULL;
+    }
+
+    sprintf(url, REGISTER_URL, domain);
+    return url;
+}
+
+static char *get_register_req()
+{
+    char *req;
+    json_t *json_root;
+
+    json_root = json_pack_ex(NULL, 1, "{s:s, s:s, s:s}", "client_name",
+            CLIENT_NAME, "redirect_uris", "urn:ietf:wg:oauth:2.0:oob", "scopes",
+            "read write push");
+    if (!json_root) {
+        return NULL;
+    }
+
+    req = json_dumps(json_root, 0);
+    json_decref(json_root);
+
+    return req;
+}
+
+static struct gs_app *get_register_resp(const char *data)
+{
+    struct gs_app *resp;
+    json_t *json_root;
+    json_t *cid, *csec;
+
+    json_root = json_loads(data, 0, NULL);
+    if (!json_root) {
+        return NULL;
+    }
+
+    if (!json_is_object(json_root)) {
+        json_decref(json_root);
+        return NULL;
+    }
+
+    cid = json_object_get(json_root, "client_id");
+    csec = json_object_get(json_root, "client_secret");
+    if (!json_is_string(cid) || !json_is_string(csec)) {
+        json_decref(json_root);
+        return NULL;
+    }
+
+    resp = calloc(1, sizeof(struct gs_app));
+    resp->client_id = strdup(json_string_value(cid));
+    resp->client_secret = strdup(json_string_value(csec));
+
+    json_decref(json_root);
+    return resp;
+}
+
+struct gs_app *gs_app_register(const char *domain)
+{
+    char *url, *req_data, *resp_data;
+    struct gs_app *resp;
+
+    if (!domain || !*domain) {
+        gs_log(GS_WARNING, "gs_app_register", "invalid argument");
+        return NULL;
+    }
+
+    url = get_register_url(domain);
+    if (!url) {
+        gs_log(GS_WARNING, "gs_app_register", "invalid argument");
+        return NULL;
+    }
+
+    req_data = get_register_req();
+    if (!req_data) {
+        free(url);
+        return NULL;
+    }
+
+    resp_data = gs_http_post(url, NULL, req_data);
+    free(url);
+    free(req_data);
+    if (!resp_data) {
+        gs_log(GS_WARNING, "gs_app_register", "register request failed");
+        return NULL;
+    }
+
+    resp = get_register_resp(resp_data);
+    free(resp_data);
+    if (!resp) {
+        gs_log(GS_WARNING, "gs_app_register", "invalid response");
+        return NULL;
+    }
+
+    return resp;
+}
diff --git a/libgs/src/app.h b/libgs/src/app.h
new file mode 100644
index 0000000..f7b6e8a
--- /dev/null
+++ b/libgs/src/app.h
@@ -0,0 +1,13 @@
+#ifndef __GS_APP_H
+#define __GS_APP_H
+
+struct gs_app {
+    char *client_id;
+    char *client_secret;
+};
+
+struct gs_app *gs_app_register(const char *domain);
+
+#endif
+
+
diff --git a/libgs/src/auth.c b/libgs/src/auth.c
new file mode 100644
index 0000000..88ab7b7
--- /dev/null
+++ b/libgs/src/auth.c
@@ -0,0 +1,109 @@
+#define _POSIX_C_SOURCE 200809L
+#include <err.h>
+#include <string.h>
+#include <jansson.h>
+#include "auth.h"
+#include "client.h"
+#include "log.h"
+#include "string-util.h"
+
+struct login_response {
+    char *access_token;
+    char *scope;
+};
+
+static char *get_login_req(const char *client_id, const char *client_secret,
+        const char *email, const char *password)
+{
+    char *req;
+    json_t *json_root;
+    json_error_t error;
+
+    json_root = json_pack_ex(&error, 1, "{s:s, s:s, s:s, s:s, s:s}",
+            "client_id", client_id, "client_secret",
+            client_secret, "grant_type", "password", "username", email,
+            "password", password);
+    if (!json_root) {
+        return NULL;
+    }
+
+    req = json_dumps(json_root, 0);
+    json_decref(json_root);
+
+    return req;
+}
+
+static struct login_response *get_login_resp(char *data)
+{
+    struct login_response *resp;
+    json_t *json_root;
+    json_t *access_token, *scope;
+
+    json_root = json_loads(data, 0, NULL);
+    if (!json_root) {
+        return NULL;
+    }
+
+    if (!json_is_object(json_root)) {
+        json_decref(json_root);
+        return NULL;
+    }
+
+    access_token = json_object_get(json_root, "access_token");
+    scope = json_object_get(json_root, "scope");
+    if (!json_is_string(access_token) || !json_is_string(scope)) {
+        json_decref(json_root);
+        return NULL;
+    }
+
+    resp = calloc(1, sizeof(struct login_response));
+    resp->access_token = strdup(json_string_value(access_token));
+    resp->scope = strdup(json_string_value(scope));
+
+    json_decref(json_root);
+    return resp;
+}
+
+int gs_auth_authenticate(GSClient *c, const char *email, const char *password)
+{
+    char *req_data, *resp_data;
+    struct login_response *resp;
+
+    if (!email || !*email || !password || !*password) {
+        gs_log(GS_WARNING, "gs_auth_authenticate", "invalid argument");
+        return -1;
+    }
+
+    req_data = get_login_req(c->client_id, c->client_secret, email, password);
+    if (!req_data) {
+        gs_log(GS_WARNING, "gs_auth_authenticate", "invalid argument");
+        return -1;
+    }
+
+    resp_data = (char *)gs_client_do_api(c, 2, "/oauth/token", req_data);
+    free(req_data);
+    if (!resp_data) {
+        gs_log(GS_WARNING, "gs_auth_authenticate", "invalid response");
+        return -1;
+    }
+
+    resp = get_login_resp(resp_data);
+    free(resp_data);
+    if (!resp) {
+        gs_log(GS_WARNING, "gs_auth_authenticate", "invalid response");
+        return -1;
+    }
+
+    gs_client_set_token(c, resp->access_token);
+
+    free(resp->access_token);
+    free(resp->scope);
+    free(resp);
+
+    return 0;
+}
+
+bool gs_auth_is_logged_in(GSClient *c)
+{
+    return c->access_token != NULL;
+}
diff --git a/libgs/src/auth.h b/libgs/src/auth.h
new file mode 100644
index 0000000..431e0d7
--- /dev/null
+++ b/libgs/src/auth.h
@@ -0,0 +1,12 @@
+#ifndef __GS_AUTH_H
+#define __GS_AUTH_H
+
+#include <stdbool.h>
+#include "client.h"
+
+int gs_auth_authenticate(GSClient *c, const char *email, const char *password);
+bool gs_auth_is_logged_in(GSClient *c);
+
+
+#endif
+
diff --git a/libgs/src/client.c b/libgs/src/client.c
new file mode 100644
index 0000000..7c0b62c
--- /dev/null
+++ b/libgs/src/client.c
@@ -0,0 +1,72 @@
+#define _POSIX_C_SOURCE 200809L
+
+#include <err.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdio.h>
+#include "client.h"
+#include "http.h"
+#include "log.h"
+#include "string-util.h"
+
+GSClient *gs_client_new(const char *server, const char *client_id, 
+        const char *client_secret)
+{
+    GSClient *c;
+
+    c = calloc(1, sizeof(GSClient));
+    if (!c) {
+        err(1, "gs_new_client");
+        return NULL;
+    }
+
+    c->server = strdup(server);
+    c->client_id = strdup(client_id);
+    c->client_secret = strdup(client_secret);
+
+    return c;
+}
+
+void *gs_client_do_api(GSClient *c, int method, const char *url, 
+        const char *req)
+{
+    char *resp;
+
+    size_t s = strlen(c->server) + strlen(url) + 1;
+    char full_url[s];
+    strlcpy(full_url, c->server, s);
+    strlcat(full_url, url, s);
+
+    switch (method) {
+        case 1:
+            resp = gs_http_get(full_url, c->access_token);
+            break;
+        case 2:
+            resp = gs_http_post(full_url, c->access_token, req);
+            break;
+        default:
+            gs_log(GS_WARNING, "gs_client_do_api", "invalid api method");
+            return NULL;
+    }
+
+    return resp;
+}
+
+void gs_client_set_token(GSClient *c, const char *access_token)
+{
+    c->access_token = strdup(access_token);
+}
+
+void gs_client_free(GSClient *c)
+{
+    if (!c) 
+        return;
+    if (c->server)
+        free(c->server);
+    if (c->client_id)
+        free(c->client_id);
+    if (c->client_secret)
+        free(c->client_secret);
+    if (c->access_token)
+        free(c->access_token);
+}
diff --git a/libgs/src/client.h b/libgs/src/client.h
new file mode 100644
index 0000000..d24b1ff
--- /dev/null
+++ b/libgs/src/client.h
@@ -0,0 +1,29 @@
+#ifndef __GS_CLIENT_H
+#define __GS_CLIENT_H
+
+typedef struct {
+    char *server;
+    char *client_id;
+    char *client_secret;
+    char *access_token;
+} GSClient;
+
+/*
+ * Create new GSClient with server url, client_id and client_secret returned
+ * from gs_register call.
+ * It will add `http://` prefix to server if it doesn't exists.
+ */
+GSClient *gs_client_new(const char *server, const char *client_id, 
+        const char *client_secret);
+
+/* Generic helper fuction to make http calls */
+void *gs_client_do_api(GSClient *c, int method, const char *url, 
+        const char *req);
+
+/* Set user access_token */
+void gs_client_set_token(GSClient *c, const char *access_token);
+
+/* Free GSClient */
+void gs_client_free(GSClient *c);
+
+#endif
diff --git a/libgs/src/config.c b/libgs/src/config.c
new file mode 100644
index 0000000..167c9af
--- /dev/null
+++ b/libgs/src/config.c
@@ -0,0 +1,174 @@
+#define _POSIX_C_SOURCE 200809L
+#include <string.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <err.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <unistd.h>
+#include <limits.h>
+#include <libgen.h>
+#include <jansson.h>
+#include "string-util.h"
+#include "config.h"
+#include "log.h"
+
+#define CONFIG_PATH_SUFFIX "/.config/ap_client/config"
+
+struct config _config;
+const struct config *config = (const struct config *)&_config;
+
+bool is_logged_in()
+{
+    if (!(config->access_token) || !*(config->access_token) ||
+            !(config->instance_url) || !*(config->instance_url)) {
+        return false;
+    }
+    return true;
+}
+
+const char *get_access_token()
+{
+    return (const char *)config->access_token;
+}
+
+const char *get_instance_url()
+{
+    return (const char *)config->instance_url;
+}
+
+bool is_registered()
+{
+    if (!(_config.client_id) || !*(_config.client_id) ||
+            !(_config.client_secret) || !*(_config.client_secret) ||
+            !(_config.instance_url) || !*(_config.instance_url)) {
+        return false;
+    }
+    return true;
+}
+
+char *get_config_path()
+{
+    char *home = getenv("HOME");
+    if (!home || !*home) {
+        return NULL;
+    }
+    char config_path[PATH_MAX];
+    strlcpy(config_path, home, sizeof(config_path));
+    strlcat(config_path, CONFIG_PATH_SUFFIX, sizeof(config_path));
+    return strdup(config_path);
+}
+
+void config_load()
+{
+    json_t *root;
+    json_error_t error;
+
+    char *path = get_config_path();
+    root = json_load_file(path, 0, &error);
+    if (!root) {
+        gs_log(GS_WARNING, "config_load", "json parse error: line %d: %s",
+                error.line, error.text);
+        free(path);
+        return;
+    }
+    free(path);
+
+    if (!json_is_object(root)) {
+        gs_log(GS_WARNING, "config_load", "json root is not object");
+        json_decref(root);
+        return;
+    }
+
+    json_t *instance_url = json_object_get(root, "instance_url");
+    if (json_is_string(instance_url)) {
+        _config.instance_url = strdup(json_string_value(instance_url));
+    }
+
+    json_t *client_id = json_object_get(root, "client_id");
+    if (json_is_string(client_id)) {
+        _config.client_id = strdup(json_string_value(client_id));
+    }
+
+    json_t *client_secret = json_object_get(root, "client_secret");
+    if (json_is_string(client_secret)) {
+        _config.client_secret = strdup(json_string_value(client_secret));
+    }
+
+    json_t *access_token = json_object_get(root, "access_token");
+    if (json_is_string(access_token)) {
+        _config.access_token = strdup(json_string_value(access_token));
+    }
+
+    json_decref(root);
+}
+
+int config_save()
+{
+    json_t *root;
+    json_error_t error;
+
+    root = json_pack_ex(&error, 1, "{s:s, s:s, s:s, s:s}", "instance_url",
+            _config.instance_url, "client_id", _config.client_id,
+            "client_secret", _config.client_secret, "access_token",
+            _config.access_token);
+
+    if (!root) {
+        gs_log(GS_WARNING, "register_app", "json pack error: line %d: %s",
+                error.line, error.text);
+        return -1;
+    }
+
+    char *config_path = get_config_path();
+    struct stat st;
+    char *dir = dirname(config_path);
+    if (stat(dir, &st)) {
+        if (mkdir(dir, S_IRWXU)) {
+            free(config_path);
+            gs_log(GS_WARNING, "config_save", "failed to create config dir");
+            return -1;
+        }
+    }
+    free(config_path);
+
+    if (json_dump_file(root, get_config_path(), 0)) {
+        gs_log(GS_WARNING, "config_save", "unable to save json");
+        json_decref(root);
+        return -1;
+    }
+
+    json_decref(root);
+    return 0;
+}
+
+void config_set_client_id(const char *cid)
+{
+    _config.client_id = strdup(cid);
+}
+
+void config_set_client_secret(const char *cs)
+{
+    _config.client_secret = strdup(cs);
+}
+
+void config_set_instance_url(const char *iu)
+{
+    _config.instance_url = strdup(iu);
+}
+
+void config_set_access_token(const char *a)
+{
+    _config.access_token = strdup(a);
+}
+
+void config_cleanup()
+{
+    if (_config.client_id)
+        free(_config.client_id);
+    if (_config.client_secret)
+        free(_config.client_secret);
+    if (_config.instance_url)
+        free(_config.instance_url);
+    if (_config.access_token)
+        free(_config.access_token);
+}
diff --git a/libgs/src/config.h b/libgs/src/config.h
new file mode 100644
index 0000000..dd1f38d
--- /dev/null
+++ b/libgs/src/config.h
@@ -0,0 +1,28 @@
+#ifndef __GS_CONFIG_H
+#define __GS_CONFIG_H
+
+#include <stdbool.h>
+
+struct gs_config {
+    char *instance_url;
+    char *client_id;
+    char *client_secret;
+    char *access_token;
+};
+
+extern const struct gs_config *config;
+
+bool gs_is_logged_in();
+const char* gs_get_access_token();
+const char* gs_get_instance_url();
+int gs_read_local_credentials();
+bool gs_is_registered();
+void gs_config_load();
+int gs_config_save();
+void gs_config_set_client_id(const char *cid);
+void gs_config_set_client_secret(const char *cs);
+void gs_config_set_instance_url(const char *iu);
+void gs_config_set_access_token(const char *a);
+void gs_config_cleanup();
+
+#endif
diff --git a/libgs/src/gs.c b/libgs/src/gs.c
new file mode 100644
index 0000000..587de59
--- /dev/null
+++ b/libgs/src/gs.c
@@ -0,0 +1,13 @@
+#define _POSIX_C_SOURCE 200809L
+#include "gs.h"
+#include "http.h"
+
+int gs_init()
+{
+    return gs_http_init();
+}
+
+void gs_cleanup()
+{
+    gs_http_cleanup();
+}
diff --git a/libgs/src/gs.h b/libgs/src/gs.h
new file mode 100644
index 0000000..c69ca40
--- /dev/null
+++ b/libgs/src/gs.h
@@ -0,0 +1,17 @@
+#ifndef __GS_H
+#define __GS_H
+
+#include "app.h" 
+#include "account.h" 
+#include "auth.h" 
+#include "client.h" 
+#include "http.h" 
+#include "log.h" 
+#include "string-util.h" 
+#include "status.h" 
+#include "timeline.h" 
+
+int gs_init();
+void gs_cleanup();
+
+#endif
diff --git a/libgs/src/http.c b/libgs/src/http.c
new file mode 100644
index 0000000..e1224ff
--- /dev/null
+++ b/libgs/src/http.c
@@ -0,0 +1,178 @@
+#define _POSIX_C_SOURCE 200809L
+#include <stdlib.h>
+#include <string.h>
+#include <pthread.h>
+#include <err.h>
+#include <curl/curl.h>
+#include "string-util.h"
+#include "auth.h"
+#include "client.h"
+#include "log.h"
+
+#define BUFFER_SIZE (256 * 1024)
+#define AUTH_HEADER_STR_PREFIX "Authorization: Bearer "
+
+int gs_http_init()
+{
+    if (curl_global_init(CURL_GLOBAL_ALL)) {
+        gs_log(GS_WARNING, "http_init", "failed to init curl");
+        return  -1;
+    }
+    return 0;
+}
+
+void gs_http_cleanup()
+{
+    curl_global_cleanup();
+    return;
+}
+
+struct write_result {
+    char *data;
+    int pos;
+};
+
+static size_t write_response(void *ptr, size_t size, size_t nmemb, void *stream)
+{
+    struct write_result *result = (struct write_result *)stream;
+
+    if (result->pos + size * nmemb >= BUFFER_SIZE - 1) {
+        gs_log(GS_WARNING, "write_response", "buffer too small");
+        return 0;
+    }
+
+    memcpy(result->data + result->pos, ptr, size * nmemb);
+    result->pos += size * nmemb;
+
+    return size * nmemb;
+}
+
+char *gs_http_get(const char *url, const char *token)
+{
+    CURL *curl = NULL;
+    CURLcode status;
+    struct curl_slist *headers = NULL;
+    char *data = NULL;
+    long code;
+
+    curl = curl_easy_init();
+    if (!curl)
+        goto error;
+
+    data = malloc(BUFFER_SIZE);
+    if (!data)
+        goto error;
+
+    struct write_result write_result = {.data = data, .pos = 0};
+
+    if (token) {
+        size_t s = strlen(AUTH_HEADER_STR_PREFIX) + strlen(token) + 1;
+        char auth_header_val[s];
+        strlcpy(auth_header_val, AUTH_HEADER_STR_PREFIX, s);
+        strlcat(auth_header_val, token, s);
+        headers = curl_slist_append(headers, auth_header_val);
+    }
+
+    curl_easy_setopt(curl, CURLOPT_URL, url);
+    curl_easy_setopt(curl, CURLOPT_HTTPHEADER, headers);
+    curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, write_response);
+    curl_easy_setopt(curl, CURLOPT_WRITEDATA, &write_result);
+
+    status = curl_easy_perform(curl);
+    if (status) {
+        gs_log(GS_WARNING, "get_request",
+                "unable to request data from %s: %s", url,
+                curl_easy_strerror(status));
+        goto error;
+    }
+
+    curl_easy_getinfo(curl, CURLINFO_RESPONSE_CODE, &code);
+    if (code != 200) {
+        gs_log(GS_WARNING, "get_request", "server responded with code %ld",
+                code);
+        goto error;
+    }
+
+    data[write_result.pos] = '\0';
+
+    curl_slist_free_all(headers);
+    curl_easy_cleanup(curl);
+    return data;
+
+error:
+    if (data)
+        free(data);
+    if (headers)
+        curl_slist_free_all(headers);
+    if (curl)
+        curl_easy_cleanup(curl);
+    return NULL;
+}
+
+char *gs_http_post(const char *url, const char *token, const char *post_data)
+{
+    CURL *curl = NULL;
+    CURLcode status;
+    struct curl_slist *headers = NULL;
+    char *data = NULL;
+    long code;
+
+    curl = curl_easy_init();
+    if (!curl)
+        goto error;
+
+    data = malloc(BUFFER_SIZE);
+    if (!data)
+        goto error;
+
+    struct write_result write_result = {.data = data, .pos = 0};
+
+    if (token) {
+        size_t s = strlen(AUTH_HEADER_STR_PREFIX) + strlen(token) + 1;
+        char auth_header_val[s];
+        strlcpy(auth_header_val, AUTH_HEADER_STR_PREFIX, s);
+        strlcat(auth_header_val, token, s);
+        headers = curl_slist_append(headers, auth_header_val);
+    }
+    if (post_data) {
+        char *content_type_header_val = "Content-Type: application/json";
+        headers = curl_slist_append(headers, content_type_header_val);
+    }
+
+    curl_easy_setopt(curl, CURLOPT_URL, url);
+    curl_easy_setopt(curl, CURLOPT_HTTPHEADER, headers);
+    curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, write_response);
+    curl_easy_setopt(curl, CURLOPT_WRITEDATA, &write_result);
+    if (post_data)
+        curl_easy_setopt(curl, CURLOPT_POSTFIELDS, post_data);
+
+    status = curl_easy_perform(curl);
+    if (status) {
+        gs_log(GS_WARNING, "post_request", 
+                "unable to request data from %s: %s",
+                url, curl_easy_strerror(status));
+        goto error;
+    }
+
+    curl_easy_getinfo(curl, CURLINFO_RESPONSE_CODE, &code);
+    if (code != 200) {
+        gs_log(GS_WARNING, "post_request", "server responded with code %ld", 
+                code);
+        goto error;
+    }
+
+    data[write_result.pos] = '\0';
+
+    curl_slist_free_all(headers);
+    curl_easy_cleanup(curl);
+    return data;
+
+error:
+    if (data)
+        free(data);
+    if (headers)
+        curl_slist_free_all(headers);
+    if (curl)
+        curl_easy_cleanup(curl);
+    return NULL;
+}
diff --git a/libgs/src/http.h b/libgs/src/http.h
new file mode 100644
index 0000000..a0d850d
--- /dev/null
+++ b/libgs/src/http.h
@@ -0,0 +1,9 @@
+#ifndef __GS_HTTP_H
+#define __GS_HTTP_H
+
+int gs_http_init();
+void gs_http_cleanup();
+char *gs_http_get(const char *url, const char *token);
+char *gs_http_post(const char *url, const char *token, const char *data);
+
+#endif
diff --git a/libgs/src/instance_info.c b/libgs/src/instance_info.c
new file mode 100644
index 0000000..40f07c6
--- /dev/null
+++ b/libgs/src/instance_info.c
@@ -0,0 +1,38 @@
+#define _POSIX_C_SOURCE 200809L
+#include <string.h>
+#include <jansson.h>
+#include "instance_info.h"
+#include "log.h"
+
+struct instance_info *instance_info_from_json(char *json_data)
+{
+    struct instance_info *info;
+    info = malloc(sizeof(struct instance_info));
+
+    json_t *root;
+    json_error_t error;
+
+    root = json_loads(json_data, 0, &error);
+
+    if (!root) {
+        gs_log(GS_WARNING, "instance_info_from_json", "error: on line %d: %s",
+                error.line, error.text);
+        return NULL;
+    }
+
+    if (!json_is_object(root)) {
+        gs_log(GS_WARNING, "instance_info_from_json", "root is not object");
+        json_decref(root);
+        return NULL;
+    }
+
+    json_t *title = json_object_get(root, "title");
+    if (!json_is_string(title)) {
+        gs_log(GS_WARNING, "instance_info_from_json", "title is not string");
+        return NULL;
+    }
+    info->title = strdup(json_string_value(title));
+
+    json_decref(root);
+    return info;
+}
diff --git a/libgs/src/instance_info.h b/libgs/src/instance_info.h
new file mode 100644
index 0000000..cdb6e84
--- /dev/null
+++ b/libgs/src/instance_info.h
@@ -0,0 +1,31 @@
+#ifndef __GS_INSTANCE_INFO_H
+#define __GS_INSTANCE_INFO_H
+
+#include <stdbool.h>
+
+struct instance_info_urls {
+    char *streaming_api;
+};
+
+struct instance_info_stats {
+    int user_count;
+    int status_count;
+    int domain_count;
+};
+
+struct instance_info {
+    char *url;
+    char *title;
+    char *description;
+    char *email;
+    char *version;
+    struct instance_info_urls urls;
+    struct instance_info_stats states;
+    char *thumbnail;
+    char **languages;
+    bool registrations;
+};
+
+struct instance_info *instance_info_from_json(char *json_data);
+
+#endif
diff --git a/libgs/src/log.c b/libgs/src/log.c
new file mode 100644
index 0000000..dad6d66
--- /dev/null
+++ b/libgs/src/log.c
@@ -0,0 +1,30 @@
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include "log.h"
+
+static const char *log_levels[] = {
+	"info",
+	"warning",
+	"error",
+	"fatal",
+};
+
+void gs_log(enum gs_log_level level, const char *namespace, 
+        const char *format, ...) {
+	va_list args;
+	va_start(args, format);
+
+	fprintf(stderr, "%s: %s: ", log_levels[level], namespace);
+	vfprintf(stderr, format, args);
+	fprintf(stderr, "\n");
+
+	if (level == GS_ERROR) {
+		exit(EXIT_FAILURE);
+	} else if (level == GS_FATAL) {
+		abort();
+	}
+
+	va_end(args);
+}
+
diff --git a/libgs/src/log.h b/libgs/src/log.h
new file mode 100644
index 0000000..83e3784
--- /dev/null
+++ b/libgs/src/log.h
@@ -0,0 +1,13 @@
+#ifndef __GS_LOG_H
+#define __GS_LOG_H
+
+enum gs_log_level {
+	GS_INFO = 0,
+	GS_WARNING,
+	GS_ERROR,
+	GS_FATAL
+};
+
+void gs_log(enum gs_log_level level, const char *namespace, const char *format, ...);
+
+#endif
diff --git a/libgs/src/status.c b/libgs/src/status.c
new file mode 100644
index 0000000..5bcdb74
--- /dev/null
+++ b/libgs/src/status.c
@@ -0,0 +1,120 @@
+#define _POSIX_C_SOURCE 200809L
+#include <err.h>
+#include <string.h>
+#include <jansson.h>
+#include "status.h"
+#include "account.h"
+#include "log.h"
+
+struct gs_status *gs_status_from_json(const char *json_data)
+{
+    struct gs_status *s;
+    json_t *root;
+    json_error_t error;
+
+    root = json_loads(json_data, 0, &error);
+    if (!root) {
+        gs_log(GS_WARNING, "status_from_json", 
+                "json parse error: line %d: %s", error.line, error.text);
+        return NULL;
+    }
+
+    s = gs_status_from_json_t(root);
+    json_decref(root);
+    return s;
+}
+
+struct gs_status *gs_status_from_json_t(const json_t *root)
+{
+    struct gs_status *s;
+    if (!root) {
+        gs_log(GS_WARNING, "gs_status_from_json_t", "json data is null");
+        return NULL;
+    }
+
+    if (!json_is_object(root)) {
+        gs_log(GS_WARNING, "gs_status_from_json_t", "json root is not object");
+        return NULL;
+    }
+
+    s = calloc(1, sizeof(struct gs_status));
+    if (!s) {
+        err(1, "gs_status_from_json_t");
+        return NULL;
+    }
+
+    json_t *id = json_object_get(root, "id");
+    if (json_is_string(id)) {
+        s->id = strdup(json_string_value(id));
+    }
+
+    json_t *uri = json_object_get(root, "uri");
+    if (json_is_string(uri)) {
+        s->uri = strdup(json_string_value(uri));
+    }
+
+    json_t *url = json_object_get(root, "url");
+    if (json_is_string(url)) {
+        s->url = strdup(json_string_value(url));
+    }
+
+    json_t *account = json_object_get(root, "account");
+    if (json_is_object(account)) {
+        s->account = gs_account_from_json_t(account);
+    }
+
+    json_t *in_reply_to_id = json_object_get(root, "in_reply_to_id");
+    if (json_is_string(in_reply_to_id)) {
+        s->in_reply_to_id = strdup(json_string_value(in_reply_to_id));
+    }
+
+    json_t *in_reply_to_account_id =
+            json_object_get(root, "in_reply_to_account_id");
+    if (json_is_string(in_reply_to_account_id)) {
+        s->in_reply_to_account_id =
+                strdup(json_string_value(in_reply_to_account_id));
+    }
+
+    json_t *content = json_object_get(root, "content");
+    if (json_is_string(content)) {
+        s->content = strdup(json_string_value(content));
+    }
+
+    json_t *replies_count = json_object_get(root, "replies_count");
+    if (json_is_integer(replies_count)) {
+        s->replies_count = json_integer_value(replies_count);
+    }
+
+    json_t *reblogs_count = json_object_get(root, "reblogs_count");
+    if (json_is_integer(reblogs_count)) {
+        s->reblogs_count = json_integer_value(reblogs_count);
+    }
+
+    json_t *favourites_count = json_object_get(root, "favourites_count");
+    if (json_is_integer(favourites_count)) {
+        s->favourites_count = json_integer_value(favourites_count);
+    }
+
+    return s;
+}
+
+void gs_status_free(struct gs_status *s)
+{
+    if (s->id)
+        free(s->id);
+    if (s->uri)
+        free(s->uri);
+    if (s->url)
+        free(s->url);
+    if (s->account)
+        gs_account_free(s->account);
+    if (s->in_reply_to_id)
+        free(s->in_reply_to_id);
+    if (s->in_reply_to_account_id)
+        free(s->in_reply_to_account_id);
+    if (s->reblog)
+        gs_status_free(s->reblog);
+    if (s->content)
+        free(s->content);
+    free(s);
+}
diff --git a/libgs/src/status.h b/libgs/src/status.h
new file mode 100644
index 0000000..431a027
--- /dev/null
+++ b/libgs/src/status.h
@@ -0,0 +1,31 @@
+#ifndef __GS_STATUS_H
+#define __GS_STATUS_H
+
+#include <stdbool.h>
+#include <jansson.h>
+
+#include "account.h"
+
+struct gs_status {
+    char *id;
+    char *uri;
+    char *url;
+    struct gs_account *account;
+    char *in_reply_to_id;
+    char *in_reply_to_account_id;
+    struct gs_status *reblog;
+    char *content;
+    unsigned int replies_count;
+    unsigned int reblogs_count;
+    unsigned int favourites_count;
+    bool reblogged;
+    bool favourited;
+    bool muted;
+    bool sensitive;
+};
+
+struct gs_status *gs_status_from_json(const char *);
+struct gs_status *gs_status_from_json_t(const json_t *);
+void gs_status_free(struct gs_status *);
+
+#endif
diff --git a/libgs/src/string-util.c b/libgs/src/string-util.c
new file mode 100644
index 0000000..7f151ae
--- /dev/null
+++ b/libgs/src/string-util.c
@@ -0,0 +1,86 @@
+/*	$OpenBSD: src/lib/libc/string/strlcpy.c,v 1.11 2006/05/05 15:27:38
+ * millert Exp $	*/
+
+/*
+ * Copyright (c) 1998 Todd C. Miller <Todd.Miller@courtesan.com>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <sys/types.h>
+#include <string.h>
+#include <stdlib.h>
+
+/*
+ * Copy src to string dst of size siz.  At most siz-1 characters
+ * will be copied.  Always NUL terminates (unless siz == 0).
+ * Returns strlen(src); if retval >= siz, truncation occurred.
+ */
+size_t strlcpy(char *dst, const char *src, size_t siz)
+{
+    char *d = dst;
+    const char *s = src;
+    size_t n = siz;
+
+    /* Copy as many bytes as will fit */
+    if (n != 0) {
+        while (--n != 0) {
+            if ((*d++ = *s++) == '\0')
+                break;
+        }
+    }
+
+    /* Not enough room in dst, add NUL and traverse rest of src */
+    if (n == 0) {
+        if (siz != 0)
+            *d = '\0'; /* NUL-terminate dst */
+        while (*s++)
+            ;
+    }
+
+    return (s - src - 1); /* count does not include NUL */
+}
+
+/*
+ * Appends src to string dst of size siz (unlike strncat, siz is the
+ * full size of dst, not space left).  At most siz-1 characters
+ * will be copied.  Always NUL terminates (unless siz <= strlen(dst)).
+ * Returns strlen(src) + MIN(siz, strlen(initial dst)).
+ * If retval >= siz, truncation occurred.
+ */
+size_t strlcat(char *dst, const char *src, size_t siz)
+{
+    char *d = dst;
+    const char *s = src;
+    size_t n = siz;
+    size_t dlen;
+
+    /* Find the end of dst and adjust bytes left but don't go past end */
+    while (n-- != 0 && *d != '\0')
+        d++;
+    dlen = d - dst;
+    n = siz - dlen;
+
+    if (n == 0)
+        return (dlen + strlen(s));
+    while (*s != '\0') {
+        if (n != 1) {
+            *d++ = *s;
+            n--;
+        }
+        s++;
+    }
+    *d = '\0';
+
+    return (dlen + (s - src)); /* count does not include NUL */
+}
diff --git a/libgs/src/string-util.h b/libgs/src/string-util.h
new file mode 100644
index 0000000..6acee6d
--- /dev/null
+++ b/libgs/src/string-util.h
@@ -0,0 +1,10 @@
+#ifndef __GS_STRING_UTIL_H
+#define __GS_STRING_UTIL_H
+
+#include <sys/types.h>
+
+size_t strlcpy(char *dst, const char *src, size_t siz);
+size_t strlcat(char *dst, const char *src, size_t siz);
+char *str_replace(const char *str, const char *old, const char *new);
+
+#endif
diff --git a/libgs/src/timeline.c b/libgs/src/timeline.c
new file mode 100644
index 0000000..fa0a2e8
--- /dev/null
+++ b/libgs/src/timeline.c
@@ -0,0 +1,93 @@
+#define _POSIX_C_SOURCE 200809L
+#include <err.h>
+#include <string.h>
+#include <pthread.h>
+#include <jansson.h>
+#include "timeline.h"
+#include "auth.h"
+#include "config.h"
+#include "http.h"
+#include "string-util.h"
+#include "log.h"
+
+struct gs_timeline *gs_timeline_from_json(const char *json_data)
+{
+    struct gs_timeline *t;
+    json_t *root;
+    json_error_t error;
+
+    root = json_loads(json_data, 0, &error);
+    if (!root) {
+        gs_log(GS_WARNING, "timeline_from_json", "json root it null");
+        return NULL;
+    }
+
+    if (!json_is_array(root)) {
+        gs_log(GS_WARNING, "timeline_from_json", "json root is not array");
+        json_decref(root);
+        return NULL;
+    }
+
+    t = calloc(1, sizeof(struct gs_timeline));
+    if (!t) {
+        err(1, NULL);
+        json_decref(root);
+        return NULL;
+    }
+
+    t->size = json_array_size(root);
+    t->statuses = calloc(t->size, sizeof(struct status *));
+    if (!(t->statuses)) {
+        err(1, NULL);
+        gs_timeline_free(t);
+        json_decref(root);
+        return NULL;
+    }
+
+    json_t *data;
+    for (size_t i = 0; i < t->size; i++) {
+        data = json_array_get(root, i);
+        if (!data)
+            goto error;
+        t->statuses[i] = gs_status_from_json_t(data);
+        if (!(t->statuses[i]))
+            goto error;
+    }
+    json_decref(root);
+    return t;
+
+error:
+    gs_timeline_free(t);
+    json_decref(root);
+    return NULL;
+}
+
+void gs_timeline_free(struct gs_timeline *t)
+{
+    for (size_t i = 0; i < t->size; i++) {
+        if (t->statuses[i])
+            gs_status_free(t->statuses[i]);
+    }
+    free(t->statuses);
+    free(t);
+}
+
+struct gs_timeline *gs_timeline_get(GSClient *c, const char *max_id, 
+        const char *since_id, const char *min_id, int limit)
+{
+    char *resp;
+    struct gs_timeline *t;
+
+    resp = (char *)gs_client_do_api(c, 1, "/api/v1/timelines/home", NULL);
+    if (!resp) {
+        return NULL;
+    }
+
+    t = gs_timeline_from_json(resp);
+    free(resp);
+    if (!t) {
+        return NULL;
+    }
+
+    return t;
+}
diff --git a/libgs/src/timeline.h b/libgs/src/timeline.h
new file mode 100644
index 0000000..73f46bb
--- /dev/null
+++ b/libgs/src/timeline.h
@@ -0,0 +1,17 @@
+#ifndef __GS_TIMELINE_H
+#define __GS_TIMELINE_H
+
+#include "status.h"
+#include "client.h"
+
+struct gs_timeline {
+    struct gs_status **statuses;
+    size_t size;
+};
+
+struct gs_timeline *gs_timeline_get(GSClient *c, const char *max_id, 
+        const char *since_id, const char *min_id, int limit);
+struct gs_timeline *gs_timeline_from_json(const char *);
+void gs_timeline_free(struct gs_timeline *);
+
+#endif