Squashed 'third_party/osqp/' content from commit 33454b3e23

Change-Id: I056df0582ca06664e86554c341a94c47ab932001
git-subtree-dir: third_party/osqp
git-subtree-split: 33454b3e236f1f44193bfbbb6b8c8e71f8f04e9a
Signed-off-by: Austin Schuh <austin.linux@gmail.com>
diff --git a/lin_sys/direct/pardiso/pardiso_interface.h b/lin_sys/direct/pardiso/pardiso_interface.h
new file mode 100644
index 0000000..c0e334d
--- /dev/null
+++ b/lin_sys/direct/pardiso/pardiso_interface.h
@@ -0,0 +1,127 @@
+#ifndef PARDISO_H
+#define PARDISO_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include "lin_alg.h"
+#include "kkt.h"
+
+/**
+ * Pardiso solver structure
+ *
+ * NB: If we use Pardiso, we suppose that EMBEDDED is not enabled
+ */
+typedef struct pardiso pardiso_solver;
+
+struct pardiso {
+    enum linsys_solver_type type;
+
+    /**
+     * @name Functions
+     * @{
+     */
+    c_int (*solve)(struct pardiso * self, c_float * b);
+
+    void (*free)(struct pardiso * self); ///< Free workspace (only if desktop)
+
+    c_int (*update_matrices)(struct pardiso * self, const csc *P, const csc *A);    ///< Update solver matrices
+    c_int (*update_rho_vec)(struct pardiso * self, const c_float * rho_vec);        ///< Update rho_vec parameter
+
+    c_int nthreads;
+    /** @} */
+
+
+    /**
+     * @name Attributes
+     * @{
+     */
+    // Attributes
+    csc *KKT;               ///< KKT matrix (in CSR format!)
+    c_int *KKT_i;           ///< KKT column indices in 1-indexing for Pardiso
+    c_int *KKT_p;           ///< KKT row pointers in 1-indexing for Pardiso
+    c_float *bp;            ///< workspace memory for solves (rhs)
+    c_float *sol;           ///< solution to the KKT system
+    c_float *rho_inv_vec;   ///< parameter vector
+    c_float sigma;          ///< scalar parameter
+    c_int polish;           ///< polishing flag
+    c_int n;                ///< number of QP variables
+    c_int m;                ///< number of QP constraints
+
+    // Pardiso variables
+    void *pt[64];     ///< internal solver memory pointer pt
+    c_int iparm[64];  ///< Pardiso control parameters
+    c_int nKKT;       ///< dimension of the linear system
+    c_int mtype;      ///< matrix type (-2 for real and symmetric indefinite)
+    c_int nrhs;       ///< number of right-hand sides (1 for our needs)
+    c_int maxfct;     ///< maximum number of factors (1 for our needs)
+    c_int mnum;       ///< indicates matrix for the solution phase (1 for our needs)
+    c_int phase;      ///< control the execution phases of the solver
+    c_int error;      ///< the error indicator (0 for no error)
+    c_int msglvl;     ///< Message level information (0 for no output)
+    c_int idum;       ///< dummy integer
+    c_float fdum;     ///< dummy float
+
+    // These are required for matrix updates
+    c_int * Pdiag_idx, Pdiag_n;  ///< index and number of diagonal elements in P
+    c_int * PtoKKT, * AtoKKT;    ///< Index of elements from P and A to KKT matrix
+    c_int * rhotoKKT;            ///< Index of rho places in KKT matrix
+
+    /** @} */
+};
+
+
+/**
+ * Initialize Pardiso Solver
+ *
+ * @param  s         Pointer to a private structure
+ * @param  P         Cost function matrix (upper triangular form)
+ * @param  A         Constraints matrix
+ * @param  sigma     Algorithm parameter. If polish, then sigma = delta.
+ * @param  rho_vec   Algorithm parameter. If polish, then rho_vec = OSQP_NULL.
+ * @param  polish    Flag whether we are initializing for polish or not
+ * @return           Exitflag for error (0 if no errors)
+ */
+c_int init_linsys_solver_pardiso(pardiso_solver ** sp, const csc * P, const csc * A, c_float sigma, const c_float * rho_vec, c_int polish);
+
+
+/**
+ * Solve linear system and store result in b
+ * @param  s        Linear system solver structure
+ * @param  b        Right-hand side
+ * @return          Exitflag
+ */
+c_int solve_linsys_pardiso(pardiso_solver * s, c_float * b);
+
+
+/**
+ * Update linear system solver matrices
+ * @param  s        Linear system solver structure
+ * @param  P        Matrix P
+ * @param  A        Matrix A
+ * @return          Exitflag
+ */
+c_int update_linsys_solver_matrices_pardiso(pardiso_solver * s, const csc *P, const csc *A);
+
+
+/**
+ * Update rho parameter in linear system solver structure
+ * @param  s        Linear system solver structure
+ * @param  rho_vec  new rho_vec value
+ * @return          exitflag
+ */
+c_int update_linsys_solver_rho_vec_pardiso(pardiso_solver * s, const c_float * rho_vec);
+
+
+/**
+ * Free linear system solver
+ * @param s linear system solver object
+ */
+void free_linsys_solver_pardiso(pardiso_solver * s);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif