Fix invalid access when highlighting basename of threads.

Process.c

@@ -405,14 +405,13 @@ static inline void Process_writeCommand(Process* this, int attr, int baseattr, R
    RichString_append(str, attr, this->comm);
    if (this->pl->highlightBaseName) {
       int finish = RichString_size(str) - 1;
-      int space = start + this->basenameOffset;
-      if (space != -1)
-         finish = space - 1;
+      if (this->basenameOffset != -1)
+         finish = (start + this->basenameOffset) - 1;
       int colon = RichString_findChar(str, ':', start);
       if (colon != -1 && colon < finish) {
          finish = colon;
       } else {
-         for (int i = finish - start; i > 0; i--) {
+         for (int i = finish - start; i >= 0; i--) {
             if (this->comm[i] == '/') {
                start += i+1;
                break;
@@ -648,6 +647,7 @@ Process* Process_new(struct ProcessList_ *pl) {
    this->utime = 0;
    this->stime = 0;
    this->comm = NULL;
+   this->basenameOffset = -1;
    this->indent = 0;
 #ifdef HAVE_CGROUP
    this->cgroup = NULL;

ProcessList.c

@@ -708,10 +708,10 @@ static bool ProcessList_readCmdlineFile(Process* process, const char* dirname, c
    if (tokenEnd == 0) {
       tokenEnd = amtRead;
    }
-   process->basenameOffset = tokenEnd;
    command[amtRead] = '\0';
    free(process->comm);
    process->comm = strdup(command);
+   process->basenameOffset = tokenEnd;
 
    return true;
 }
@@ -831,10 +831,12 @@ static bool ProcessList_processEntries(ProcessList* this, const char* dirname, P
 
       if (process->state == 'Z') {
          free(process->comm);
+         process->basenameOffset = -1;
          process->comm = strdup(command);
       } else if (Process_isThread(process)) {
          if (this->showThreadNames || Process_isKernelThread(process) || process->state == 'Z') {
             free(process->comm);
+            process->basenameOffset = -1;
             process->comm = strdup(command);
          } else if (this->showingThreadNames) {
             if (! ProcessList_readCmdlineFile(process, dirname, name))
@@ -858,6 +860,7 @@ static bool ProcessList_processEntries(ProcessList* this, const char* dirname, P
       errorReadingProcess: {
          if (process->comm) {
             free(process->comm);
+            process->basenameOffset = -1;
             process->comm = NULL;
          }
          if (existingProcess)