There’s a good run down of Texas’ rules for filibuster here (which gives you a better idea of the massive, heroic task that Wendy Davis undertook for her state). But as has been discussed in the comments here, these rules for filibuster seem remarkably, shockingly ableist. Conditions laid down for filibuster include:
Rule 3.02 prohibits eating or drinking in the Senate chamber.
Rule 4.01 requires a member of the Senate to stand at his or her desk to address the Senate. The member speaking may not sit, lean, or use a desk or chair in any way. Bathroom breaks are not allowed.
Rule 4.03, which governs the interruption of a member who is speaking, allows other senators to raise objections if a speaker does not confine his or her remarks to the issue under consideration or if his or her voice is inaudible.
So you cannot filibuster if you are a wheelchair user. You cannot filibuster if you are hypoglycemic. You cannot filibuster if you use various types of mobility aid. You cannot filibuster if you have such a stunning array of disabilities that the mind boggles.
How is the legal? That’s not rhetoic, that’s a serious question. How are these rules not a flagrant violation of the ADA?