load chatlog history when opening a chatwindow

src/chat.c

@@ -1091,8 +1091,11 @@ static void chat_onInit(ToxWindow *self, Tox *m)
 
     line_info_init(ctx->hst);
 
-    if (Friends.list[self->num].logging_on)
     log_enable(nick, Friends.list[self->num].pub_key, ctx->log);
+    load_chat_history(self, ctx->log);
+
+    if (!Friends.list[self->num].logging_on)
+        log_disable(ctx->log);
 
     execute(ctx->history, self, m, "/log", GLOBAL_COMMAND_MODE);
 

src/line_info.c

@@ -135,7 +135,7 @@ void line_info_add(ToxWindow *self, char *timestr, char *name1, char *name2, uin
 {
     struct history *hst = self->chatwin->hst;
 
-    if (hst->queue_sz >= MAX_QUEUE)
+    if (hst->queue_sz >= MAX_LINE_INFO_QUEUE)
         return;
 
     struct line_info *new_line = calloc(1, sizeof(struct line_info));

src/line_info.h

@@ -28,7 +28,7 @@
 
 #define MAX_HISTORY 100000
 #define MIN_HISTORY 40
-#define MAX_QUEUE 128
+#define MAX_LINE_INFO_QUEUE 512
 
 enum {
     SYS_MSG,
@@ -68,7 +68,7 @@ struct history {
     struct line_info *line_end;
     uint32_t start_id;    /* keeps track of where line_start should be when at bottom of history */
 
-    struct line_info *queue[MAX_QUEUE];
+    struct line_info *queue[MAX_LINE_INFO_QUEUE];
     int queue_sz;
 };
 

src/log.c

@@ -23,6 +23,7 @@
 #include <stdlib.h>
 #include <string.h>
 #include <time.h>
+#include <sys/stat.h>
 
 #include "configdir.h"
 #include "toxic.h"
@@ -30,6 +31,7 @@
 #include "misc_tools.h"
 #include "log.h"
 #include "settings.h"
+#include "line_info.h"
 
 extern struct user_settings *user_settings_;
 
@@ -76,14 +78,13 @@ void init_logging_session(char *name, const char *key, struct chatlog *log)
 
     free(user_config_dir);
 
-    log->file = fopen(log_path, "a");
+    log->file = fopen(log_path, "a+");
+    snprintf(log->path, sizeof(log->path), "%s", log_path);
 
     if (log->file == NULL) {
         log->log_on = false;
         return;
     }
-
-    fprintf(log->file, "\n*** NEW SESSION ***\n\n");
 }
 
 #define LOG_FLUSH_LIMIT 1  /* limits calls to fflush to a max of one per LOG_FLUSH_LIMIT seconds */
@@ -135,3 +136,60 @@ void log_disable(struct chatlog *log)
         log->file = NULL;
     }
 }
+
+/* Loads previous history from chat log */
+void load_chat_history(ToxWindow *self, struct chatlog *log)
+{
+    if (log->file == NULL)
+        return;
+
+    struct stat st;
+
+    if (stat(log->path, &st) == -1) {
+        line_info_add(self, NULL, NULL, NULL, SYS_MSG, 0, RED, "* Failed to stat log file");
+        return;
+    }
+
+    int sz = st.st_size;
+
+    if (sz <= 0)
+        return;
+
+    char *hstbuf = malloc(sz);
+
+    if (hstbuf == NULL)
+        exit_toxic_err("failed in print_prev_chat_history", FATALERR_MEMORY);
+
+    if (fread(hstbuf, sz, 1, log->file) != 1) {
+        free(hstbuf);
+        line_info_add(self, NULL, NULL, NULL, SYS_MSG, 0, RED, "* Failed to read log file");
+        return;
+    }
+
+    /* Number of history lines to load: must not be larger than MAX_LINE_INFO_QUEUE - 2 */
+    int L = MIN(MAX_LINE_INFO_QUEUE - 2, user_settings_->history_size);
+    int start, count = 0;
+
+    /* start at end and backtrace L lines or to the beginning of buffer */
+    for (start = sz - 1; start >= 0 && count < L; --start) {
+        if (hstbuf[start] == '\n')
+            ++count;
+    }
+
+    char buf[MAX_STR_SIZE];
+    const char *line = strtok(&hstbuf[start + 1], "\n");
+
+    if (line == NULL) {
+        free(hstbuf);
+        return;
+    }
+
+    while (line != NULL) {
+        snprintf(buf, sizeof(buf), "%s", line);
+        line_info_add(self, NULL, NULL, NULL, SYS_MSG, 0, 0, "%s", buf);
+        line = strtok(NULL, "\n");
+    }
+
+    line_info_add(self, NULL, NULL, NULL, SYS_MSG, 0, 0, "");
+    free(hstbuf);
+}

src/log.h

@@ -26,6 +26,7 @@
 struct chatlog {
     FILE *file;
     uint64_t lastwrite;
+    char path[MAX_STR_SIZE];
     bool log_on;    /* specific to current chat window */
 };
 
@@ -41,4 +42,7 @@ void log_enable(char *name, const char *key, struct chatlog *log);
 /* disables logging for specified log and closes file */
 void log_disable(struct chatlog *log);
 
+/* Loads previous history from chat log */
+void load_chat_history(ToxWindow *self, struct chatlog *log);
+
 #endif /* #define _log_h */