Is a defendant entitled to credit against his sentence for his time in custody?

Pursuant to section 2900.5, a person sentenced to state prison for criminal conduct is entitled to credit against the term of imprisonment for all days spent in custody before sentencing. ( 2900.5, subd.(a).) In addition, section 4019 provides that a criminal defendant may earn additional presentence credit against his or her sentence for willingness to perform assigned labor ( 4019, subd. (b)) and compliance with rules and regulations ( 4019, subd. (c)). These forms of presentence credit are collectively called "'conduct credit.'" (People v. Dieck (2009) 46 Cal.4th 934, 939, fn. 3.)