rply.c

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/* ----------------------------------------------------------------------
 * RPly library, read/write PLY files
 * Diego Nehab, Princeton University
 * http://www.cs.princeton.edu/~diego/professional/rply
 *
 * This library is distributed under the MIT License. See notice
 * at the end of this file.
 * ---------------------------------------------------------------------- */
#include <stdio.h>
#include <ctype.h>
#include <assert.h>
#include <string.h>
#include <limits.h>
#include <float.h>
#include <stdarg.h>
#include <stdlib.h>
#include <stddef.h>

#include "rply.h"

/* ----------------------------------------------------------------------
 * Constants 
 * ---------------------------------------------------------------------- */
#define WORDSIZE 256
#define LINESIZE 1024
#define BUFFERSIZE (8*1024)

typedef enum e_ply_io_mode_ {
    PLY_READ, 
    PLY_WRITE
} e_ply_io_mode;

static const char *const ply_storage_mode_list[] = {
    "binary_big_endian", "binary_little_endian", "ascii", NULL
};     /* order matches e_ply_storage_mode enum */

static const char *const ply_type_list[] = {
    "int8", "uint8", "int16", "uint16", 
    "int32", "uint32", "float32", "float64",
    "char", "uchar", "short", "ushort", 
    "int", "uint", "float", "double",
    "list", NULL
};     /* order matches e_ply_type enum */

/* ----------------------------------------------------------------------
 * Property reading callback argument
 *
 * element: name of element being processed
 * property: name of property being processed
 * nelements: number of elements of this kind in file
 * instance_index: index current element of this kind being processed
 * length: number of values in current list (or 1 for scalars)
 * value_index: index of current value int this list (or 0 for scalars)
 * value: value of property
 * pdata/idata: user data defined with ply_set_cb
 *
 * Returns handle to ply file if succesful, NULL otherwise.
 * ---------------------------------------------------------------------- */
typedef struct t_ply_argument_ {
    p_ply_element element;
    long instance_index;
    p_ply_property property;
    long length, value_index;
    double value;
    void *pdata;
    long idata;
} t_ply_argument;

/* ----------------------------------------------------------------------
 * Property information
 *
 * name: name of this property
 * type: type of this property (list or type of scalar value)
 * length_type, value_type: type of list property count and values
 * read_cb: function to be called when this property is called
 *
 * Returns 1 if should continue processing file, 0 if should abort.
 * ---------------------------------------------------------------------- */
typedef struct t_ply_property_ {
    char name[WORDSIZE];
    e_ply_type type, value_type, length_type;
    p_ply_read_cb read_cb;
    void *pdata;
    long idata;
} t_ply_property; 

/* ----------------------------------------------------------------------
 * Element information
 *
 * name: name of this property
 * ninstances: number of elements of this type in file
 * property: property descriptions for this element
 * nproperty: number of properties in this element
 *
 * Returns 1 if should continue processing file, 0 if should abort.
 * ---------------------------------------------------------------------- */
typedef struct t_ply_element_ {
    char name[WORDSIZE];
    long ninstances;
    p_ply_property property;
    long nproperties;
} t_ply_element;

/* ----------------------------------------------------------------------
 * Input/output driver
 *
 * Depending on file mode, different functions are used to read/write 
 * property fields. The drivers make it transparent to read/write in ascii, 
 * big endian or little endian cases.
 * ---------------------------------------------------------------------- */
typedef int (*p_ply_ihandler)(p_ply ply, double *value);
typedef int (*p_ply_ichunk)(p_ply ply, void *anydata, size_t size);
typedef struct t_ply_idriver_ {
    p_ply_ihandler ihandler[16];
    p_ply_ichunk ichunk;
    const char *name;
} t_ply_idriver;
typedef t_ply_idriver *p_ply_idriver;

typedef int (*p_ply_ohandler)(p_ply ply, double value);
typedef int (*p_ply_ochunk)(p_ply ply, void *anydata, size_t size);
typedef struct t_ply_odriver_ {
    p_ply_ohandler ohandler[16];
    p_ply_ochunk ochunk;
    const char *name;
} t_ply_odriver;
typedef t_ply_odriver *p_ply_odriver;

/* ----------------------------------------------------------------------
 * Ply file handle. 
 *
 * io_mode: read or write (from e_ply_io_mode)
 * storage_mode: mode of file associated with handle (from e_ply_storage_mode)
 * element: elements description for this file
 * nelement: number of different elements in file
 * comment: comments for this file
 * ncomments: number of comments in file
 * obj_info: obj_info items for this file
 * nobj_infos: number of obj_info items in file
 * fp: file pointer associated with ply file
 * c: last character read from ply file
 * buffer: last word/chunck of data read from ply file
 * buffer_first, buffer_last: interval of untouched good data in buffer
 * buffer_token: start of parsed token (line or word) in buffer
 * idriver, odriver: input driver used to get property fields from file 
 * argument: storage space for callback arguments
 * welement, wproperty: element/property type being written
 * winstance_index: index of instance of current element being written
 * wvalue_index: index of list property value being written 
 * wlength: number of values in list property being written
 * error_cb: callback for error messages
 * ---------------------------------------------------------------------- */
typedef struct t_ply_ {
    e_ply_io_mode io_mode;
    e_ply_storage_mode storage_mode;
    p_ply_element element;
    long nelements;
    char *comment;
    long ncomments;
    char *obj_info;
    long nobj_infos;
    FILE *fp;
    int c;
    char buffer[BUFFERSIZE];
    size_t buffer_first, buffer_token, buffer_last;
    p_ply_idriver idriver;
    p_ply_odriver odriver;
    t_ply_argument argument;
    long welement, wproperty;
    long winstance_index, wvalue_index, wlength;
    p_ply_error_cb error_cb;
} t_ply;

/* ----------------------------------------------------------------------
 * I/O functions and drivers
 * ---------------------------------------------------------------------- */
static t_ply_idriver ply_idriver_ascii;
static t_ply_idriver ply_idriver_binary;
static t_ply_idriver ply_idriver_binary_reverse;
static t_ply_odriver ply_odriver_ascii;
static t_ply_odriver ply_odriver_binary;
static t_ply_odriver ply_odriver_binary_reverse;

static int ply_read_word(p_ply ply);
static int ply_check_word(p_ply ply);
static int ply_read_line(p_ply ply);
static int ply_check_line(p_ply ply);
static int ply_read_chunk(p_ply ply, void *anybuffer, size_t size);
static int ply_read_chunk_reverse(p_ply ply, void *anybuffer, size_t size);
static int ply_write_chunk(p_ply ply, void *anybuffer, size_t size);
static int ply_write_chunk_reverse(p_ply ply, void *anybuffer, size_t size);
static void ply_reverse(void *anydata, size_t size);

/* ----------------------------------------------------------------------
 * String functions
 * ---------------------------------------------------------------------- */
static int ply_find_string(const char *item, const char* const list[]);
static p_ply_element ply_find_element(p_ply ply, const char *name);
static p_ply_property ply_find_property(p_ply_element element, 
        const char *name);

/* ----------------------------------------------------------------------
 * Header parsing
 * ---------------------------------------------------------------------- */
static int ply_read_header_format(p_ply ply);
static int ply_read_header_comment(p_ply ply);
static int ply_read_header_obj_info(p_ply ply);
static int ply_read_header_property(p_ply ply);
static int ply_read_header_element(p_ply ply);

/* ----------------------------------------------------------------------
 * Error handling
 * ---------------------------------------------------------------------- */
static void ply_error_cb(const char *message);
static void ply_error(p_ply ply, const char *fmt, ...);

/* ----------------------------------------------------------------------
 * Memory allocation and initialization
 * ---------------------------------------------------------------------- */
static void ply_init(p_ply ply);
static void ply_element_init(p_ply_element element);
static void ply_property_init(p_ply_property property);
static p_ply ply_alloc(void);
static p_ply_element ply_grow_element(p_ply ply);
static p_ply_property ply_grow_property(p_ply ply, p_ply_element element);
static void *ply_grow_array(p_ply ply, void **pointer, long *nmemb, long size);

/* ----------------------------------------------------------------------
 * Special functions
 * ---------------------------------------------------------------------- */
static e_ply_storage_mode ply_arch_endian(void);
static int ply_type_check(void); 

/* ----------------------------------------------------------------------
 * Auxiliary read functions
 * ---------------------------------------------------------------------- */
static int ply_read_element(p_ply ply, p_ply_element element, 
        p_ply_argument argument);
static int ply_read_property(p_ply ply, p_ply_element element, 
        p_ply_property property, p_ply_argument argument);
static int ply_read_list_property(p_ply ply, p_ply_element element, 
        p_ply_property property, p_ply_argument argument);
static int ply_read_scalar_property(p_ply ply, p_ply_element element, 
        p_ply_property property, p_ply_argument argument);


/* ----------------------------------------------------------------------
 * Buffer support functions
 * ---------------------------------------------------------------------- */
/* pointers to tokenized word and line in buffer */
#define BWORD(p) (p->buffer + p->buffer_token)
#define BLINE(p) (p->buffer + p->buffer_token)

/* pointer to start of untouched bytes in buffer */
#define BFIRST(p) (p->buffer + p->buffer_first) 

/* number of bytes untouched in buffer */
#define BSIZE(p) (p->buffer_last - p->buffer_first) 

/* consumes data from buffer */
#define BSKIP(p, s) (p->buffer_first += s)

/* refills the buffer */
static int BREFILL(p_ply ply) {
    /* move untouched data to beginning of buffer */
    size_t size = BSIZE(ply);
    memmove(ply->buffer, BFIRST(ply), size);
    ply->buffer_last = size;
    ply->buffer_first = ply->buffer_token = 0;
    /* fill remaining with new data */
    size = fread(ply->buffer+size, 1, BUFFERSIZE-size-1, ply->fp);
    /* place sentinel so we can use str* functions with buffer */
    ply->buffer[BUFFERSIZE-1] = '\0';
    /* check if read failed */
    if (size <= 0) return 0;
    /* increase size to account for new data */
    ply->buffer_last += size;
    return 1;
}

/* ----------------------------------------------------------------------
 * Exported functions
 * ---------------------------------------------------------------------- */
/* ----------------------------------------------------------------------
 * Read support functions
 * ---------------------------------------------------------------------- */
p_ply ply_open(const char *name, p_ply_error_cb error_cb) {
    char magic[5] = "    ";
    FILE *fp = NULL; 
    p_ply ply = NULL;
    if (error_cb == NULL) error_cb = ply_error_cb;
    if (!ply_type_check()) {
        error_cb("Incompatible type system");
        return NULL;
    }
    assert(name);
    fp = fopen(name, "rb");
    if (!fp) {
        error_cb("Unable to open file");
        return NULL;
    }
    if (fread(magic, 1, 4, fp) < 4) {
        error_cb("Error reading from file");
        fclose(fp);
        return NULL;
    }
    if (strcmp(magic, "ply\n")) {
        fclose(fp);
        error_cb("Not a PLY file. Expected magic number 'ply\\n'");
        return NULL;
    }
    ply = ply_alloc();
    if (!ply) {
        error_cb("Out of memory");
        fclose(fp);
        return NULL;
    }
    ply->fp = fp;
    ply->io_mode = PLY_READ;
    ply->error_cb = error_cb;
    return ply;
}

int ply_read_header(p_ply ply) {
    assert(ply && ply->fp && ply->io_mode == PLY_READ);
    if (!ply_read_word(ply)) return 0;
    /* parse file format */
    if (!ply_read_header_format(ply)) {
        ply_error(ply, "Invalid file format");
        return 0;
    }
    /* parse elements, comments or obj_infos until the end of header */
    while (strcmp(BWORD(ply), "end_header")) {
        if (!ply_read_header_comment(ply) && 
                !ply_read_header_element(ply) && 
                !ply_read_header_obj_info(ply)) {
            ply_error(ply, "Unexpected token '%s'", BWORD(ply));
            return 0;
        }
    }
    return 1;
}

long ply_set_read_cb(p_ply ply, const char *element_name, 
        const char* property_name, p_ply_read_cb read_cb, 
        void *pdata, long idata) {
    p_ply_element element = NULL; 
    p_ply_property property = NULL;
    assert(ply && element_name && property_name);
    element = ply_find_element(ply, element_name);
    if (!element) return 0;
    property = ply_find_property(element, property_name);
    if (!property) return 0;
    property->read_cb = read_cb;
    property->pdata = pdata;
    property->idata = idata;
    return (int) element->ninstances;
}

int ply_read(p_ply ply) {
    long i;
    p_ply_argument argument;
    assert(ply && ply->fp && ply->io_mode == PLY_READ);
    argument = &ply->argument;
    /* for each element type */
    for (i = 0; i < ply->nelements; i++) {
        p_ply_element element = &ply->element[i];
        argument->element = element;
        if (!ply_read_element(ply, element, argument))
            return 0;
    }
    return 1;
}

/* ----------------------------------------------------------------------