Fossil

** Append text to the header of an HTTP reply
*/
void cgi_append_header(const char *zLine){
  blob_append(&extraHeader, zLine, -1);
}

/*
** Set a cookie by queuing up the appropriate HTTP header output. If
** !g.isHTTP, this is a no-op.
**
** Zero lifetime implies a session cookie.
*/
void cgi_set_cookie(
  const char *zName,    /* Name of the cookie */
  const char *zValue,   /* Value of the cookie.  Automatically escaped */
  const char *zPath,    /* Path cookie applies to.  NULL means "/" */
  int lifetime          /* Expiration of the cookie in seconds from now */
){
  char const *zSecure = "";
  if(!g.isHTTP) return /* e.g. JSON CLI mode, where g.zTop is not set */;
  else if( zPath==0 ){
    zPath = g.zTop;
    if( zPath[0]==0 ) zPath = "/";
  }
  if( g.zBaseURL!=0 && strncmp(g.zBaseURL, "https:", 6)==0 ){
    zSecure = " secure;";
  }
  if( lifetime>0 ){

  int rid;               /* Artifact ID of the file being annotated */
  int fnid;              /* Filename ID */
  Stmt q;                /* Query returning all ancestor versions */
  int cnt = 0;           /* Number of versions analyzed */
  int iLimit;            /* Maximum number of versions to analyze */
  sqlite3_int64 mxTime;  /* Halt at this time if not already complete */

  memset(p, 0, sizeof(*p));

  if( zLimit ){
    if( strcmp(zLimit,"none")==0 ){
      iLimit = 0;
      mxTime = 0;
    }else if( sqlite3_strglob("*[0-9]s", zLimit)==0 ){
      iLimit = 0;
      mxTime = current_time_in_milliseconds() + 1000.0*atof(zLimit);
    }else{
      iLimit = atoi(zLimit);
      if( iLimit<=0 ) iLimit = 30;
      mxTime = 0;
    }
  }else{
    /* Default limit is as much as we can do in 1.000 seconds */
    iLimit = 0;
    mxTime = current_time_in_milliseconds()+1000;
  }
  db_begin_transaction();

  /* Get the artifact ID for the check-in begin analyzed */
  if( zRevision ){
    cid = name_to_typed_rid(zRevision, "ci");
  }else{
    db_must_be_within_tree();
    cid = db_lget_int("checkout", 0);
  }
  origid = zOrigin ? name_to_typed_rid(zOrigin, "ci") : 0;

      blob_to_utf8_no_bom(&step, 0);
      annotation_step(p, &step, p->nVers-1, annFlags);
      blob_reset(&step);
    }
    p->nVers++;
    cnt++;
  }

  if( p->nVers==0 ){
    if( zRevision ){
      fossil_fatal("file %s does not exist in check-in %s", zFilename, zRevision);
    }else{
      fossil_fatal("no history for file: %s", zFilename);
    }
  }

  db_finalize(&q);
  db_end_transaction(0);
}

/*
** Return a color from a gradient.
*/

  Th_Store("compiler_name", COMPILER_NAME);
  url_var("stylesheet", "css", "style.css");
  image_url_var("logo");
  image_url_var("background");
  if( !login_is_nobody() ){
    Th_Store("login", g.zLogin);
  }
  if( sqlite3_strlike("%<body%", zHeader, 0)!=0 ){
    Th_Render(zDfltHeader);
  }
  if( g.thTrace ) Th_Trace("BEGIN_HEADER_SCRIPT<br />\n", -1);
  Th_Render(zHeader);
  if( g.thTrace ) Th_Trace("END_HEADER<br />\n", -1);
  Th_Unstore("title");   /* Avoid collisions with ticket field names */
  cgi_destination(CGI_BODY);

When cloning a repository, the skin of new repository is initialized to
the skin of the repository from which it was cloned.

Header And Footer Processing
----------------------------

The header.txt and footer.txt files of a skin are merely the HTML text
of the header and footer.  Except, before being prepended and appended to
the content, the header and footer text are run through a
[TH1 interpreter](./th1.md) that might adjust the text as follows:

  *  All text within <th1>...</th1> is elided from the
     output and that text is instead run as a TH1 script.  That TH1
     script has the opportunity to insert new text in place of itself,